diff --git a/camera/aidl/android/hardware/ICameraServiceProxy.aidl b/camera/aidl/android/hardware/ICameraServiceProxy.aidl
index 88783fb..fefea13 100644
--- a/camera/aidl/android/hardware/ICameraServiceProxy.aidl
+++ b/camera/aidl/android/hardware/ICameraServiceProxy.aidl
@@ -48,5 +48,5 @@
     /**
      * Checks if the camera has been disabled via device policy.
      */
-    boolean isCameraDisabled();
+    boolean isCameraDisabled(int userId);
 }
diff --git a/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp b/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
index 32d7723..e04dd7e 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
+++ b/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
@@ -619,6 +619,7 @@
         return Void();
     }
 
+    Mutex::Autolock lock(mSecurityLevelLock);
     std::map<std::vector<uint8_t>, SecurityLevel>::iterator itr =
             mSecurityLevel.find(sid);
     if (itr == mSecurityLevel.end()) {
@@ -691,6 +692,7 @@
         return Status::ERROR_DRM_SESSION_NOT_OPENED;
     }
 
+    Mutex::Autolock lock(mSecurityLevelLock);
     std::map<std::vector<uint8_t>, SecurityLevel>::iterator itr =
             mSecurityLevel.find(sid);
     if (itr != mSecurityLevel.end()) {
diff --git a/drm/mediadrm/plugins/clearkey/hidl/include/DrmPlugin.h b/drm/mediadrm/plugins/clearkey/hidl/include/DrmPlugin.h
index cb5c9fe..1019520 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/include/DrmPlugin.h
+++ b/drm/mediadrm/plugins/clearkey/hidl/include/DrmPlugin.h
@@ -414,7 +414,8 @@
     std::map<std::string, std::vector<uint8_t> > mByteArrayProperties;
     std::map<std::string, std::vector<uint8_t> > mReleaseKeysMap;
     std::map<std::vector<uint8_t>, std::string> mPlaybackId;
-    std::map<std::vector<uint8_t>, SecurityLevel> mSecurityLevel;
+    std::map<std::vector<uint8_t>, SecurityLevel> mSecurityLevel
+        GUARDED_BY(mSecurityLevelLock);
     sp<IDrmPluginListener> mListener;
     sp<IDrmPluginListener_V1_2> mListenerV1_2;
     SessionLibrary *mSessionLibrary;
@@ -434,6 +435,7 @@
 
     DeviceFiles mFileHandle;
     Mutex mSecureStopLock;
+    Mutex mSecurityLevelLock;
 
     CLEARKEY_DISALLOW_COPY_AND_ASSIGN_AND_NEW(DrmPlugin);
 };
diff --git a/media/codec2/hidl/1.0/utils/types.cpp b/media/codec2/hidl/1.0/utils/types.cpp
index 5c24bd7..319ba62 100644
--- a/media/codec2/hidl/1.0/utils/types.cpp
+++ b/media/codec2/hidl/1.0/utils/types.cpp
@@ -1447,6 +1447,10 @@
 bool objcpy(C2BaseBlock* d, const BaseBlock& s) {
     switch (s.getDiscriminator()) {
     case BaseBlock::hidl_discriminator::nativeBlock: {
+            if (s.nativeBlock() == nullptr) {
+                LOG(ERROR) << "Null BaseBlock::nativeBlock handle";
+                return false;
+            }
             native_handle_t* sHandle =
                     native_handle_clone(s.nativeBlock());
             if (sHandle == nullptr) {
@@ -1609,6 +1613,7 @@
     // assuming blob is const here
     size_t size = blob.size();
     size_t ix = 0;
+    size_t old_ix = 0;
     const uint8_t *data = blob.data();
     C2Param *p = nullptr;
 
@@ -1616,8 +1621,13 @@
         p = C2ParamUtils::ParseFirst(data + ix, size - ix);
         if (p) {
             params->emplace_back(p);
+            old_ix = ix;
             ix += p->size();
             ix = align(ix, PARAMS_ALIGNMENT);
+            if (ix <= old_ix || ix > size) {
+                android_errorWriteLog(0x534e4554, "238083570");
+                break;
+            }
         }
     } while (p);
 
diff --git a/media/codec2/sfplugin/CCodec.cpp b/media/codec2/sfplugin/CCodec.cpp
index 43bdb21..72301db 100644
--- a/media/codec2/sfplugin/CCodec.cpp
+++ b/media/codec2/sfplugin/CCodec.cpp
@@ -1973,7 +1973,6 @@
     }
 
     mChannel->reset();
-    mChannel->stopUseOutputSurface();
     // thiz holds strong ref to this while the thread is running.
     sp<CCodec> thiz(this);
     std::thread([thiz, sendCallback] { thiz->release(sendCallback); }).detach();
@@ -1994,6 +1993,7 @@
         comp = state->comp;
     }
     comp->release();
+    mChannel->stopUseOutputSurface();
 
     {
         Mutexed<State>::Locked state(mState);
@@ -2141,7 +2141,8 @@
 
     std::map<size_t, sp<MediaCodecBuffer>> clientInputBuffers;
     status_t err = mChannel->prepareInitialInputBuffers(&clientInputBuffers);
-    if (err != OK) {
+    // FIXME(b/237656746)
+    if (err != OK && err != NO_MEMORY) {
         ALOGE("Resume request for Input Buffers failed");
         mCallback->onError(err, ACTION_CODE_FATAL);
         return;
diff --git a/media/libaudioclient/include/media/AudioPolicy.h b/media/libaudioclient/include/media/AudioPolicy.h
index 08b3da1..fbb1100 100644
--- a/media/libaudioclient/include/media/AudioPolicy.h
+++ b/media/libaudioclient/include/media/AudioPolicy.h
@@ -137,6 +137,11 @@
            == MIX_ROUTE_FLAG_LOOP_BACK_AND_RENDER;
 }
 
+static inline bool is_mix_loopback(uint32_t routeFlags) {
+    return (routeFlags & MIX_ROUTE_FLAG_LOOP_BACK)
+           == MIX_ROUTE_FLAG_LOOP_BACK;
+}
+
 }; // namespace android
 
 #endif  // ANDROID_AUDIO_POLICY_H
diff --git a/media/libaudiohal/impl/EffectsFactoryHalHidl.cpp b/media/libaudiohal/impl/EffectsFactoryHalHidl.cpp
index d7217fc..3470380 100644
--- a/media/libaudiohal/impl/EffectsFactoryHalHidl.cpp
+++ b/media/libaudiohal/impl/EffectsFactoryHalHidl.cpp
@@ -17,6 +17,9 @@
 #define LOG_TAG "EffectsFactoryHalHidl"
 //#define LOG_NDEBUG 0
 
+#include <optional>
+#include <tuple>
+
 #include <cutils/native_handle.h>
 
 #include <UuidUtils.h>
@@ -38,51 +41,71 @@
 using namespace ::android::hardware::audio::common::CPP_VERSION;
 using namespace ::android::hardware::audio::effect::CPP_VERSION;
 
+class EffectDescriptorCache {
+  public:
+    using QueryResult = std::tuple<Return<void>, Result, hidl_vec<EffectDescriptor>>;
+    QueryResult queryAllDescriptors(IEffectsFactory* effectsFactory);
+  private:
+    std::mutex mLock;
+    std::optional<hidl_vec<EffectDescriptor>> mLastDescriptors;  // GUARDED_BY(mLock)
+};
+
+EffectDescriptorCache::QueryResult EffectDescriptorCache::queryAllDescriptors(
+        IEffectsFactory* effectsFactory) {
+    {
+        std::lock_guard l(mLock);
+        if (mLastDescriptors.has_value()) {
+            return {::android::hardware::Void(), Result::OK, mLastDescriptors.value()};
+        }
+    }
+    Result retval = Result::NOT_INITIALIZED;
+    hidl_vec<EffectDescriptor> descriptors;
+    Return<void> ret = effectsFactory->getAllDescriptors(
+            [&](Result r, const hidl_vec<EffectDescriptor>& result) {
+                retval = r;
+                if (retval == Result::OK) {
+                    descriptors = result;
+                }
+            });
+    if (ret.isOk() && retval == Result::OK) {
+        std::lock_guard l(mLock);
+        mLastDescriptors = descriptors;
+    }
+    return {std::move(ret), retval, std::move(descriptors)};
+}
+
 EffectsFactoryHalHidl::EffectsFactoryHalHidl(sp<IEffectsFactory> effectsFactory)
-        : EffectConversionHelperHidl("EffectsFactory") {
+        : EffectConversionHelperHidl("EffectsFactory"), mCache(new EffectDescriptorCache) {
     ALOG_ASSERT(effectsFactory != nullptr, "Provided IEffectsFactory service is NULL");
     mEffectsFactory = effectsFactory;
 }
 
-status_t EffectsFactoryHalHidl::queryAllDescriptors() {
-    if (mEffectsFactory == 0) return NO_INIT;
-    Result retval = Result::NOT_INITIALIZED;
-    Return<void> ret = mEffectsFactory->getAllDescriptors(
-            [&](Result r, const hidl_vec<EffectDescriptor>& result) {
-                retval = r;
-                if (retval == Result::OK) {
-                    mLastDescriptors = result;
-                }
-            });
-    if (ret.isOk()) {
-        return retval == Result::OK ? OK : NO_INIT;
-    }
-    mLastDescriptors.resize(0);
-    return processReturn(__FUNCTION__, ret);
-}
-
 status_t EffectsFactoryHalHidl::queryNumberEffects(uint32_t *pNumEffects) {
-    status_t queryResult = queryAllDescriptors();
-    if (queryResult == OK) {
-        *pNumEffects = mLastDescriptors.size();
+    if (mEffectsFactory == 0) return NO_INIT;
+    auto [ret, retval, descriptors] = mCache->queryAllDescriptors(mEffectsFactory.get());
+    if (ret.isOk() && retval == Result::OK) {
+        *pNumEffects = descriptors.size();
+        return OK;
+    } else if (ret.isOk()) {
+        return NO_INIT;
     }
-    return queryResult;
+    return processReturn(__FUNCTION__, ret);
 }
 
 status_t EffectsFactoryHalHidl::getDescriptor(
         uint32_t index, effect_descriptor_t *pDescriptor) {
-    // TODO: We need somehow to track the changes on the server side
-    // or figure out how to convert everybody to query all the descriptors at once.
     if (pDescriptor == nullptr) {
         return BAD_VALUE;
     }
-    if (mLastDescriptors.size() == 0) {
-        status_t queryResult = queryAllDescriptors();
-        if (queryResult != OK) return queryResult;
+    if (mEffectsFactory == 0) return NO_INIT;
+    auto [ret, retval, descriptors] = mCache->queryAllDescriptors(mEffectsFactory.get());
+    if (ret.isOk() && retval == Result::OK) {
+        if (index >= descriptors.size()) return NAME_NOT_FOUND;
+        EffectUtils::effectDescriptorToHal(descriptors[index], pDescriptor);
+    } else if (ret.isOk()) {
+        return NO_INIT;
     }
-    if (index >= mLastDescriptors.size()) return NAME_NOT_FOUND;
-    EffectUtils::effectDescriptorToHal(mLastDescriptors[index], pDescriptor);
-    return OK;
+    return processReturn(__FUNCTION__, ret);
 }
 
 status_t EffectsFactoryHalHidl::getDescriptor(
@@ -114,21 +137,15 @@
     if (pEffectType == nullptr || descriptors == nullptr) {
         return BAD_VALUE;
     }
+    if (mEffectsFactory == 0) return NO_INIT;
 
-    uint32_t numEffects = 0;
-    status_t status = queryNumberEffects(&numEffects);
-    if (status != NO_ERROR) {
-        ALOGW("%s error %d from FactoryHal queryNumberEffects", __func__, status);
-        return status;
+    auto [ret, retval, hidlDescs] = mCache->queryAllDescriptors(mEffectsFactory.get());
+    if (!ret.isOk() || retval != Result::OK) {
+        return processReturn(__FUNCTION__, ret, retval);
     }
-
-    for (uint32_t i = 0; i < numEffects; i++) {
+    for (const auto& hidlDesc : hidlDescs) {
         effect_descriptor_t descriptor;
-        status = getDescriptor(i, &descriptor);
-        if (status != NO_ERROR) {
-            ALOGW("%s error %d from FactoryHal getDescriptor", __func__, status);
-            continue;
-        }
+        EffectUtils::effectDescriptorToHal(hidlDesc, &descriptor);
         if (memcmp(&descriptor.type, pEffectType, sizeof(effect_uuid_t)) == 0) {
             descriptors->push_back(descriptor);
         }
diff --git a/media/libaudiohal/impl/EffectsFactoryHalHidl.h b/media/libaudiohal/impl/EffectsFactoryHalHidl.h
index e1882e1..7ccddc6 100644
--- a/media/libaudiohal/impl/EffectsFactoryHalHidl.h
+++ b/media/libaudiohal/impl/EffectsFactoryHalHidl.h
@@ -17,6 +17,8 @@
 #ifndef ANDROID_HARDWARE_EFFECTS_FACTORY_HAL_HIDL_H
 #define ANDROID_HARDWARE_EFFECTS_FACTORY_HAL_HIDL_H
 
+#include <memory>
+
 #include PATH(android/hardware/audio/effect/FILE_VERSION/IEffectsFactory.h)
 #include <media/audiohal/EffectsFactoryHalInterface.h>
 
@@ -28,6 +30,8 @@
 using ::android::hardware::hidl_vec;
 using namespace ::android::hardware::audio::effect::CPP_VERSION;
 
+class EffectDescriptorCache;
+
 class EffectsFactoryHalHidl : public EffectsFactoryHalInterface, public EffectConversionHelperHidl
 {
   public:
@@ -63,9 +67,7 @@
 
   private:
     sp<IEffectsFactory> mEffectsFactory;
-    hidl_vec<EffectDescriptor> mLastDescriptors;
-
-    status_t queryAllDescriptors();
+    std::unique_ptr<EffectDescriptorCache> mCache;
 };
 
 } // namespace effect
diff --git a/media/libheadtracking/Android.bp b/media/libheadtracking/Android.bp
index 7e2c762..f64aedf 100644
--- a/media/libheadtracking/Android.bp
+++ b/media/libheadtracking/Android.bp
@@ -83,6 +83,7 @@
         "Twist-test.cpp",
     ],
     shared_libs: [
+        "libaudioutils",
         "libheadtracking",
     ],
 }
diff --git a/media/libheadtracking/HeadTrackingProcessor.cpp b/media/libheadtracking/HeadTrackingProcessor.cpp
index fb44567..101b825 100644
--- a/media/libheadtracking/HeadTrackingProcessor.cpp
+++ b/media/libheadtracking/HeadTrackingProcessor.cpp
@@ -88,10 +88,12 @@
     }
 
     void calculate(int64_t timestamp) override {
-        // Handle the screen first, since it might trigger a recentering of the head.
+        bool screenStable = true;
+
+        // Handle the screen first, since it might: trigger a recentering of the head.
         if (mWorldToScreenTimestamp.has_value()) {
             const Pose3f worldToLogicalScreen = mScreenPoseBias.getOutput();
-            bool screenStable = mScreenStillnessDetector.calculate(timestamp);
+            screenStable = mScreenStillnessDetector.calculate(timestamp);
             mModeSelector.setScreenStable(mWorldToScreenTimestamp.value(), screenStable);
             // Whenever the screen is unstable, recenter the head pose.
             if (!screenStable) {
@@ -105,7 +107,8 @@
         if (mWorldToHeadTimestamp.has_value()) {
             Pose3f worldToHead = mHeadPoseBias.getOutput();
             // Auto-recenter.
-            if (mHeadStillnessDetector.calculate(timestamp)) {
+            bool headStable = mHeadStillnessDetector.calculate(timestamp);
+            if (headStable || !screenStable) {
                 recenter(true, false);
                 worldToHead = mHeadPoseBias.getOutput();
             }
@@ -161,29 +164,30 @@
     std::string toString_l(unsigned level) const override {
         std::string prefixSpace(level, ' ');
         std::string ss = prefixSpace + "HeadTrackingProcessor:\n";
-        StringAppendF(&ss, "%smaxTranslationalVelocity: %f\n", prefixSpace.c_str(),
+        StringAppendF(&ss, "%s maxTranslationalVelocity: %f meter/second\n", prefixSpace.c_str(),
                       mOptions.maxTranslationalVelocity);
-        StringAppendF(&ss, "%smaxRotationalVelocity: %f\n", prefixSpace.c_str(),
+        StringAppendF(&ss, "%s maxRotationalVelocity: %f rad/second\n", prefixSpace.c_str(),
                       mOptions.maxRotationalVelocity);
-        StringAppendF(&ss, "%sfreshnessTimeout: %" PRId64 "\n", prefixSpace.c_str(),
-                      mOptions.freshnessTimeout);
-        StringAppendF(&ss, "%spredictionDuration: %f\n", prefixSpace.c_str(),
-                      mOptions.predictionDuration);
-        StringAppendF(&ss, "%sautoRecenterWindowDuration: %" PRId64 "\n", prefixSpace.c_str(),
-                      mOptions.autoRecenterWindowDuration);
-        StringAppendF(&ss, "%sautoRecenterTranslationalThreshold: %f\n", prefixSpace.c_str(),
+        StringAppendF(&ss, "%s freshnessTimeout: %0.4f ms\n", prefixSpace.c_str(),
+                      media::nsToFloatMs(mOptions.freshnessTimeout));
+        StringAppendF(&ss, "%s predictionDuration: %0.4f ms\n", prefixSpace.c_str(),
+                      media::nsToFloatMs(mOptions.predictionDuration));
+        StringAppendF(&ss, "%s autoRecenterWindowDuration: %0.4f ms\n", prefixSpace.c_str(),
+                      media::nsToFloatMs(mOptions.autoRecenterWindowDuration));
+        StringAppendF(&ss, "%s autoRecenterTranslationalThreshold: %f meter\n", prefixSpace.c_str(),
                       mOptions.autoRecenterTranslationalThreshold);
-        StringAppendF(&ss, "%sautoRecenterRotationalThreshold: %f\n", prefixSpace.c_str(),
+        StringAppendF(&ss, "%s autoRecenterRotationalThreshold: %f radians\n", prefixSpace.c_str(),
                       mOptions.autoRecenterRotationalThreshold);
-        StringAppendF(&ss, "%sscreenStillnessWindowDuration: %" PRId64 "\n", prefixSpace.c_str(),
-                      mOptions.screenStillnessWindowDuration);
-        StringAppendF(&ss, "%sscreenStillnessTranslationalThreshold: %f\n", prefixSpace.c_str(),
-                      mOptions.screenStillnessTranslationalThreshold);
-        StringAppendF(&ss, "%sscreenStillnessRotationalThreshold: %f\n", prefixSpace.c_str(),
-                      mOptions.screenStillnessRotationalThreshold);
+        StringAppendF(&ss, "%s screenStillnessWindowDuration: %0.4f ms\n", prefixSpace.c_str(),
+                      media::nsToFloatMs(mOptions.screenStillnessWindowDuration));
+        StringAppendF(&ss, "%s screenStillnessTranslationalThreshold: %f meter\n",
+                      prefixSpace.c_str(), mOptions.screenStillnessTranslationalThreshold);
+        StringAppendF(&ss, "%s screenStillnessRotationalThreshold: %f radians\n",
+                      prefixSpace.c_str(), mOptions.screenStillnessRotationalThreshold);
+        ss += mModeSelector.toString(level + 1);
+        ss += mRateLimiter.toString(level + 1);
         ss.append(prefixSpace + "ReCenterHistory:\n");
         ss += mLocalLog.dumpToString((prefixSpace + " ").c_str(), mMaxLocalLogLine);
-        // TODO: 233092747 add string from PoseRateLimiter/PoseRateLimiter etc...
         return ss;
     }
 
@@ -214,5 +218,17 @@
     return std::make_unique<HeadTrackingProcessorImpl>(options, initialMode);
 }
 
+std::string toString(HeadTrackingMode mode) {
+    switch (mode) {
+        case HeadTrackingMode::STATIC:
+            return "STATIC";
+        case HeadTrackingMode::WORLD_RELATIVE:
+            return "WORLD_RELATIVE";
+        case HeadTrackingMode::SCREEN_RELATIVE:
+            return "SCREEN_RELATIVE";
+    }
+    return "EnumNotImplemented";
+};
+
 }  // namespace media
 }  // namespace android
diff --git a/media/libheadtracking/ModeSelector.cpp b/media/libheadtracking/ModeSelector.cpp
index cb3a27f..6277090 100644
--- a/media/libheadtracking/ModeSelector.cpp
+++ b/media/libheadtracking/ModeSelector.cpp
@@ -13,11 +13,13 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+#include <android-base/stringprintf.h>
 
 #include "ModeSelector.h"
 
 namespace android {
 namespace media {
+using android::base::StringAppendF;
 
 ModeSelector::ModeSelector(const Options& options, HeadTrackingMode initialMode)
     : mOptions(options), mDesiredMode(initialMode), mActualMode(initialMode) {}
@@ -47,12 +49,15 @@
 }
 
 void ModeSelector::calculateActualMode(int64_t timestamp) {
-    bool isValidScreenToHead = mScreenToHead.has_value() &&
-                               timestamp - mScreenToHeadTimestamp < mOptions.freshnessTimeout;
-    bool isValidWorldToHead = mWorldToHead.has_value() &&
-                              timestamp - mWorldToHeadTimestamp < mOptions.freshnessTimeout;
-    bool isValidScreenStable = mScreenStable.has_value() &&
-                              timestamp - mScreenStableTimestamp < mOptions.freshnessTimeout;
+    int64_t screenToHeadGap = timestamp - mScreenToHeadTimestamp;
+    int64_t worldToHeadGap = timestamp - mWorldToHeadTimestamp;
+    int64_t screenStableGap = timestamp - mScreenStableTimestamp;
+    bool isValidScreenToHead =
+            mScreenToHead.has_value() && screenToHeadGap < mOptions.freshnessTimeout;
+    bool isValidWorldToHead =
+            mWorldToHead.has_value() && worldToHeadGap < mOptions.freshnessTimeout;
+    bool isValidScreenStable =
+            mScreenStable.has_value() && screenStableGap < mOptions.freshnessTimeout;
 
     HeadTrackingMode mode = mDesiredMode;
 
@@ -70,7 +75,17 @@
         }
     }
 
-    mActualMode = mode;
+    if (mode != mActualMode) {
+        mLocalLog.log(
+                "HT mode change from %s to %s, this ts %0.4f ms, lastTs+gap [ScreenToHead %0.4f + "
+                "%0.4f, WorldToHead %0.4f + %0.4f, ScreenStable %0.4f + %0.4f] ms",
+                media::toString(mActualMode).c_str(), media::toString(mode).c_str(),
+                media::nsToFloatMs(timestamp), media::nsToFloatMs(mScreenToHeadTimestamp),
+                media::nsToFloatMs(screenToHeadGap), media::nsToFloatMs(mWorldToHeadTimestamp),
+                media::nsToFloatMs(worldToHeadGap), media::nsToFloatMs(mScreenStableTimestamp),
+                media::nsToFloatMs(screenStableGap));
+        mActualMode = mode;
+    }
 }
 
 void ModeSelector::calculate(int64_t timestamp) {
@@ -99,5 +114,15 @@
     return mActualMode;
 }
 
+std::string ModeSelector::toString(unsigned level) const {
+    std::string prefixSpace(level, ' ');
+    std::string ss(prefixSpace);
+    StringAppendF(&ss, "ModeSelector: ScreenToStage %s\n",
+                    mScreenToStage.toString().c_str());
+    ss.append(prefixSpace + "Mode downgrade history:\n");
+    ss += mLocalLog.dumpToString((prefixSpace + " ").c_str(), sMaxLocalLogLine);
+    return ss;
+}
+
 }  // namespace media
 }  // namespace android
diff --git a/media/libheadtracking/ModeSelector.h b/media/libheadtracking/ModeSelector.h
index e537040..2475a5b 100644
--- a/media/libheadtracking/ModeSelector.h
+++ b/media/libheadtracking/ModeSelector.h
@@ -16,6 +16,7 @@
 #pragma once
 
 #include <optional>
+#include <audio_utils/SimpleLog.h>
 
 #include "media/HeadTrackingMode.h"
 #include "media/Pose.h"
@@ -114,6 +115,8 @@
      */
     HeadTrackingMode getActualMode() const;
 
+    std::string toString(unsigned level) const;
+
   private:
     const Options mOptions;
 
@@ -129,6 +132,9 @@
     HeadTrackingMode mActualMode;
     Pose3f mHeadToStage;
 
+    static constexpr std::size_t sMaxLocalLogLine = 10;
+    SimpleLog mLocalLog{sMaxLocalLogLine};
+
     void calculateActualMode(int64_t timestamp);
 };
 
diff --git a/media/libheadtracking/Pose.cpp b/media/libheadtracking/Pose.cpp
index ae39512..4a4b56a 100644
--- a/media/libheadtracking/Pose.cpp
+++ b/media/libheadtracking/Pose.cpp
@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+#include <android-base/stringprintf.h>
 
 #include "media/Pose.h"
 #include "media/Twist.h"
@@ -21,6 +22,7 @@
 namespace android {
 namespace media {
 
+using android::base::StringAppendF;
 using Eigen::Vector3f;
 
 std::optional<Pose3f> Pose3f::fromVector(const std::vector<float>& vec) {
@@ -35,6 +37,19 @@
     return {mTranslation[0], mTranslation[1], mTranslation[2], rot[0], rot[1], rot[2]};
 }
 
+std::string Pose3f::toString() const {
+    const auto& vec = this->toVector();
+    std::string ss = "[";
+    for (auto f = vec.begin(); f != vec.end(); ++f) {
+        if (f != vec.begin()) {
+            ss.append(", ");
+        }
+        StringAppendF(&ss, "%0.2f", *f);
+    }
+    ss.append("]");
+    return ss;
+}
+
 std::tuple<Pose3f, bool> moveWithRateLimit(const Pose3f& from, const Pose3f& to, float t,
                                            float maxTranslationalVelocity,
                                            float maxRotationalVelocity) {
diff --git a/media/libheadtracking/PoseRateLimiter.cpp b/media/libheadtracking/PoseRateLimiter.cpp
index 380e22b..060bb4b 100644
--- a/media/libheadtracking/PoseRateLimiter.cpp
+++ b/media/libheadtracking/PoseRateLimiter.cpp
@@ -13,11 +13,13 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+#include <android-base/stringprintf.h>
 
 #include "PoseRateLimiter.h"
 
 namespace android {
 namespace media {
+using android::base::StringAppendF;
 
 PoseRateLimiter::PoseRateLimiter(const Options& options) : mOptions(options), mLimiting(false) {}
 
@@ -48,5 +50,15 @@
     return pose;
 }
 
+std::string PoseRateLimiter::toString(unsigned level) const {
+    std::string ss(level, ' ');
+    if (mLimiting) {
+        StringAppendF(&ss, "PoseRateLimiter: enabled with target: %s\n",
+                      mTargetPose.has_value() ? mTargetPose.value().toString().c_str() : "NULL");
+    } else {
+        StringAppendF(&ss, "PoseRateLimiter: disabled\n");
+    }
+    return ss;
+}
 }  // namespace media
 }  // namespace android
diff --git a/media/libheadtracking/PoseRateLimiter.h b/media/libheadtracking/PoseRateLimiter.h
index aa2fe80..c673a33 100644
--- a/media/libheadtracking/PoseRateLimiter.h
+++ b/media/libheadtracking/PoseRateLimiter.h
@@ -77,6 +77,8 @@
 
     Pose3f calculatePose(int64_t timestamp);
 
+    std::string toString(unsigned level) const;
+
   private:
     struct Point {
         Pose3f pose;
diff --git a/media/libheadtracking/SensorPoseProvider.cpp b/media/libheadtracking/SensorPoseProvider.cpp
index 6c0a96d..bd8af04 100644
--- a/media/libheadtracking/SensorPoseProvider.cpp
+++ b/media/libheadtracking/SensorPoseProvider.cpp
@@ -18,9 +18,10 @@
 
 #define LOG_TAG "SensorPoseProvider"
 
-#include <inttypes.h>
-
+#include <algorithm>
 #include <future>
+#include <inttypes.h>
+#include <limits>
 #include <map>
 #include <thread>
 
@@ -135,7 +136,10 @@
 
         {
             std::lock_guard lock(mMutex);
-            mEnabledSensorsExtra.emplace(sensor, SensorExtra{ .format = format });
+            mEnabledSensorsExtra.emplace(
+                    sensor,
+                    SensorExtra{.format = format,
+                                .samplingPeriod = static_cast<int32_t>(samplingPeriod.count())});
         }
 
         // Enable the sensor.
@@ -173,8 +177,11 @@
         StringAppendF(&ss, "%sSensors total number %zu:\n", prefixSpace.c_str(),
                       mEnabledSensorsExtra.size());
         for (auto sensor : mEnabledSensorsExtra) {
-            StringAppendF(&ss, "%s[Handle: 0x%08x, Format %s", prefixSpace.c_str(), sensor.first,
-                          toString(sensor.second.format).c_str());
+            StringAppendF(&ss,
+                          "%s[Handle: 0x%08x, Format %s Period (set %d max %0.4f min %0.4f) ms",
+                          prefixSpace.c_str(), sensor.first, toString(sensor.second.format).c_str(),
+                          sensor.second.samplingPeriod, media::nsToFloatMs(sensor.second.maxPeriod),
+                          media::nsToFloatMs(sensor.second.minPeriod));
             if (sensor.second.discontinuityCount.has_value()) {
                 StringAppendF(&ss, ", DiscontinuityCount: %d",
                               sensor.second.discontinuityCount.value());
@@ -202,7 +209,11 @@
     };
 
     struct SensorExtra {
-        DataFormat format;
+        DataFormat format = DataFormat::kUnknown;
+        int32_t samplingPeriod = 0;
+        int64_t latestTimestamp = 0;
+        int64_t maxPeriod = 0;
+        int64_t minPeriod = std::numeric_limits<int64_t>::max();
         std::optional<int32_t> discontinuityCount;
     };
 
@@ -296,6 +307,7 @@
                 return;
             }
             value = parseEvent(event, iter->second.format, &iter->second.discontinuityCount);
+            updateEventTimestamp(event, iter->second);
         }
         mListener->onPose(event.timestamp, event.sensor, value.pose, value.twist,
                           value.isNewReference);
@@ -351,6 +363,15 @@
         return std::nullopt;
     }
 
+    void updateEventTimestamp(const ASensorEvent& event, SensorExtra& extra) {
+        if (extra.latestTimestamp != 0) {
+            int64_t gap = event.timestamp - extra.latestTimestamp;
+            extra.maxPeriod = std::max(gap, extra.maxPeriod);
+            extra.minPeriod = std::min(gap, extra.minPeriod);
+        }
+        extra.latestTimestamp = event.timestamp;
+    }
+
     static PoseEvent parseEvent(const ASensorEvent& event, DataFormat format,
                                 std::optional<int32_t>* discontinutyCount) {
         switch (format) {
@@ -381,7 +402,7 @@
         }
     }
 
-    const std::string toString(DataFormat format) {
+    const static std::string toString(DataFormat format) {
         switch (format) {
             case DataFormat::kUnknown:
                 return "kUnknown";
diff --git a/media/libheadtracking/StillnessDetector.cpp b/media/libheadtracking/StillnessDetector.cpp
index be7c893..5232084 100644
--- a/media/libheadtracking/StillnessDetector.cpp
+++ b/media/libheadtracking/StillnessDetector.cpp
@@ -26,6 +26,9 @@
     mFifo.clear();
     mWindowFull = false;
     mSuppressionDeadline.reset();
+    // A "true" state indicates stillness is detected (default = true)
+    mCurrentState = true;
+    mPreviousState = true;
 }
 
 void StillnessDetector::setInput(int64_t timestamp, const Pose3f& input) {
@@ -33,7 +36,15 @@
     discardOld(timestamp);
 }
 
+bool StillnessDetector::getPreviousState() const {
+    return mPreviousState;
+}
+
 bool StillnessDetector::calculate(int64_t timestamp) {
+    // Move the current stillness state to the previous state.
+    // This allows us to detect transitions into and out of stillness.
+    mPreviousState = mCurrentState;
+
     discardOld(timestamp);
 
     // Check whether all the poses in the queue are in the proximity of the new one. We want to do
@@ -60,15 +71,17 @@
 
     // If the window has not been full, return the default value.
     if (!mWindowFull) {
-        return mOptions.defaultValue;
+        mCurrentState = mOptions.defaultValue;
     }
-
     // Force "in motion" while the suppression deadline is active.
-    if (mSuppressionDeadline.has_value()) {
-        return false;
+    else if (mSuppressionDeadline.has_value()) {
+        mCurrentState = false;
+    }
+    else {
+        mCurrentState = !moved;
     }
 
-    return !moved;
+    return mCurrentState;
 }
 
 void StillnessDetector::discardOld(int64_t timestamp) {
diff --git a/media/libheadtracking/StillnessDetector.h b/media/libheadtracking/StillnessDetector.h
index ee4b2d8..abd7cc4 100644
--- a/media/libheadtracking/StillnessDetector.h
+++ b/media/libheadtracking/StillnessDetector.h
@@ -80,7 +80,8 @@
     void setInput(int64_t timestamp, const Pose3f& input);
     /** Calculate whether the stream is still at the given timestamp. */
     bool calculate(int64_t timestamp);
-
+    /** Return the stillness state from the previous call to calculate() */
+    bool getPreviousState() const;
   private:
     struct TimestampedPose {
         int64_t timestamp;
@@ -92,6 +93,8 @@
     const float mCosHalfRotationalThreshold;
     std::deque<TimestampedPose> mFifo;
     bool mWindowFull = false;
+    bool mCurrentState = true;
+    bool mPreviousState = true;
     // As soon as motion is detected, this will be set for the time of detection + window duration,
     // and during this time we will always consider outselves in motion without checking. This is
     // used for hyteresis purposes, since because of the approximate method we use for determining
diff --git a/media/libheadtracking/include/media/HeadTrackingMode.h b/media/libheadtracking/include/media/HeadTrackingMode.h
index 38496e8..92d1165 100644
--- a/media/libheadtracking/include/media/HeadTrackingMode.h
+++ b/media/libheadtracking/include/media/HeadTrackingMode.h
@@ -15,6 +15,8 @@
  */
 #pragma once
 
+#include <string>
+
 namespace android {
 namespace media {
 
@@ -30,5 +32,7 @@
     SCREEN_RELATIVE,
 };
 
+std::string toString(HeadTrackingMode mode);
+
 }  // namespace media
 }  // namespace android
diff --git a/media/libheadtracking/include/media/Pose.h b/media/libheadtracking/include/media/Pose.h
index e660bb9..50294ed 100644
--- a/media/libheadtracking/include/media/Pose.h
+++ b/media/libheadtracking/include/media/Pose.h
@@ -16,6 +16,7 @@
 #pragma once
 
 #include <optional>
+#include <string>
 #include <vector>
 #include <Eigen/Geometry>
 
@@ -63,6 +64,9 @@
      */
     std::vector<float> toVector() const;
 
+    // Convert instance to a string representation.
+    std::string toString() const;
+
     Pose3f& operator=(const Pose3f& other) {
         mTranslation = other.mTranslation;
         mRotation = other.mRotation;
@@ -128,5 +132,10 @@
                                            float maxTranslationalVelocity,
                                            float maxRotationalVelocity);
 
+template <typename T>
+static float nsToFloatMs(T ns) {
+    return ns * 1e-6f;
+}
+
 }  // namespace media
 }  // namespace android
diff --git a/media/libmediametrics/include/MediaMetricsConstants.h b/media/libmediametrics/include/MediaMetricsConstants.h
index 1c30510..27f987d 100644
--- a/media/libmediametrics/include/MediaMetricsConstants.h
+++ b/media/libmediametrics/include/MediaMetricsConstants.h
@@ -57,6 +57,10 @@
 // The Audio Spatializer key appends the spatializerId (currently 0)
 #define AMEDIAMETRICS_KEY_PREFIX_AUDIO_SPATIALIZER AMEDIAMETRICS_KEY_PREFIX_AUDIO "spatializer."
 
+// The Audio Spatializer device key appends the device type.
+#define AMEDIAMETRICS_KEY_PREFIX_AUDIO_SPATIALIZER_DEVICE \
+        AMEDIAMETRICS_KEY_PREFIX_AUDIO_SPATIALIZER "device."
+
 // The AudioStream key appends the "streamId" to the prefix.
 #define AMEDIAMETRICS_KEY_PREFIX_AUDIO_STREAM  AMEDIAMETRICS_KEY_PREFIX_AUDIO "stream."
 
@@ -83,6 +87,7 @@
 #define AMEDIAMETRICS_PROP_PREFIX_EFFECTIVE "effective."
 #define AMEDIAMETRICS_PROP_PREFIX_HAL       "hal."
 #define AMEDIAMETRICS_PROP_PREFIX_HAPTIC    "haptic."
+#define AMEDIAMETRICS_PROP_PREFIX_LAST      "last."
 #define AMEDIAMETRICS_PROP_PREFIX_SERVER    "server."
 
 // Properties within mediametrics are string constants denoted by
@@ -107,6 +112,7 @@
 // of suppressed in the Time Machine.
 #define AMEDIAMETRICS_PROP_SUFFIX_CHAR_DUPLICATES_ALLOWED '#'
 
+#define AMEDIAMETRICS_PROP_ADDRESS        "address"        // string, for example MAC address
 #define AMEDIAMETRICS_PROP_ALLOWUID       "_allowUid"      // int32_t, allow client uid to post
 #define AMEDIAMETRICS_PROP_AUDIOMODE      "audioMode"      // string (audio.flinger)
 #define AMEDIAMETRICS_PROP_AUXEFFECTID    "auxEffectId"    // int32 (AudioTrack)
@@ -116,6 +122,8 @@
 #define AMEDIAMETRICS_PROP_CALLERNAME     "callerName"     // string, eg. "aaudio"
 #define AMEDIAMETRICS_PROP_CHANNELCOUNT   "channelCount"   // int32
 #define AMEDIAMETRICS_PROP_CHANNELMASK    "channelMask"    // int32
+#define AMEDIAMETRICS_PROP_CHANNELMASKS   "channelMasks"   // string with channelMask values
+                                                           // separated by |.
 #define AMEDIAMETRICS_PROP_CONTENTTYPE    "contentType"    // string attributes (AudioTrack)
 #define AMEDIAMETRICS_PROP_CUMULATIVETIMENS "cumulativeTimeNs" // int64_t playback/record time
                                                            // since start
@@ -132,6 +140,7 @@
 
 #define AMEDIAMETRICS_PROP_DIRECTION      "direction"      // string AAudio input or output
 #define AMEDIAMETRICS_PROP_DURATIONNS     "durationNs"     // int64 duration time span
+#define AMEDIAMETRICS_PROP_ENABLED        "enabled"        // string true/false.
 #define AMEDIAMETRICS_PROP_ENCODING       "encoding"       // string value of format
 
 #define AMEDIAMETRICS_PROP_EVENT          "event#"         // string value (often func name)
@@ -141,6 +150,8 @@
 #define AMEDIAMETRICS_PROP_FLAGS          "flags"
 
 #define AMEDIAMETRICS_PROP_FRAMECOUNT     "frameCount"     // int32
+#define AMEDIAMETRICS_PROP_HASHEADTRACKER  "hasHeadTracker" // string true/false
+#define AMEDIAMETRICS_PROP_HEADTRACKERENABLED "headTrackerEnabled" // string true/false
 #define AMEDIAMETRICS_PROP_HEADTRACKINGMODES "headTrackingModes" // string |, like modes.
 #define AMEDIAMETRICS_PROP_INPUTDEVICES   "inputDevices"   // string value
 #define AMEDIAMETRICS_PROP_INTERNALTRACKID "internalTrackId" // int32
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.cpp b/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.cpp
index 45fac76..0382df3 100644
--- a/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.cpp
+++ b/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.cpp
@@ -1947,22 +1947,12 @@
     CHECK(format->findInt32("channel-count", &numChannels));
 
     // channel mask info as read from the audio format
-    int32_t channelMaskFromFormat;
+    int32_t mediaFormatChannelMask;
     // channel mask to use for native playback
     audio_channel_mask_t channelMask;
-    if (format->findInt32("channel-mask", &channelMaskFromFormat)) {
+    if (format->findInt32("channel-mask", &mediaFormatChannelMask)) {
         // KEY_CHANNEL_MASK follows the android.media.AudioFormat java mask
-        // which is left-bitshifted by 2 relative to the native mask
-        if ((channelMaskFromFormat & 0b11) != 0) {
-            // received an unexpected mask (supposed to follow AudioFormat constants
-            // for output masks with the 2 least-significant bits at 0), but
-            // it may come from an extractor that uses native masks: keeping
-            // the mask as given is ok as it contains at least mono or stereo
-            // and potentially the haptic channels
-            channelMask = static_cast<audio_channel_mask_t>(channelMaskFromFormat);
-        } else {
-            channelMask = static_cast<audio_channel_mask_t>(channelMaskFromFormat >> 2);
-        }
+        channelMask = audio_channel_mask_from_media_format_mask(mediaFormatChannelMask);
     } else {
         // no mask found: the mask will be derived from the channel count
         channelMask = CHANNEL_MASK_USE_CHANNEL_ORDER;
diff --git a/media/libstagefright/FrameDecoder.cpp b/media/libstagefright/FrameDecoder.cpp
index 3df8766..344456c 100644
--- a/media/libstagefright/FrameDecoder.cpp
+++ b/media/libstagefright/FrameDecoder.cpp
@@ -86,11 +86,14 @@
         displayHeight = height;
     }
 
-    if (allocRotated && (rotationAngle == 90 || rotationAngle == 270)) {
-        int32_t tmp;
-        tmp = width; width = height; height = tmp;
-        tmp = displayWidth; displayWidth = displayHeight; displayHeight = tmp;
-        tmp = tileWidth; tileWidth = tileHeight; tileHeight = tmp;
+    if (allocRotated) {
+        if (rotationAngle == 90 || rotationAngle == 270) {
+            // swap width and height for 90 & 270 degrees rotation
+            std::swap(width, height);
+            std::swap(displayWidth, displayHeight);
+            std::swap(tileWidth, tileHeight);
+        }
+        // Rotation is already applied.
         rotationAngle = 0;
     }
 
diff --git a/media/utils/MethodStatistics.cpp b/media/utils/MethodStatistics.cpp
index b179b20..086757b 100644
--- a/media/utils/MethodStatistics.cpp
+++ b/media/utils/MethodStatistics.cpp
@@ -22,7 +22,8 @@
 
 std::shared_ptr<std::vector<std::string>>
 getStatisticsClassesForModule(std::string_view moduleName) {
-    static const std::map<std::string, std::shared_ptr<std::vector<std::string>>> m {
+    static const std::map<std::string, std::shared_ptr<std::vector<std::string>>,
+            std::less<> /* transparent comparator */> m {
         {
             METHOD_STATISTICS_MODULE_NAME_AUDIO_HIDL,
             std::shared_ptr<std::vector<std::string>>(
@@ -34,13 +35,14 @@
               })
         },
     };
-    auto it = m.find({moduleName.begin(), moduleName.end()});
+    auto it = m.find(moduleName);
     if (it == m.end()) return {};
     return it->second;
 }
 
 static void addClassesToMap(const std::shared_ptr<std::vector<std::string>> &classNames,
-        std::map<std::string, std::shared_ptr<MethodStatistics<std::string>>> &map) {
+        std::map<std::string, std::shared_ptr<MethodStatistics<std::string>>,
+                std::less<> /* transparent comparator */> &map) {
     if (classNames) {
         for (const auto& className : *classNames) {
             map.emplace(className, std::make_shared<MethodStatistics<std::string>>());
@@ -51,17 +53,18 @@
 // singleton statistics for DeviceHalHidl StreamOutHalHidl StreamInHalHidl
 std::shared_ptr<MethodStatistics<std::string>>
 getStatisticsForClass(std::string_view className) {
-    static const std::map<std::string, std::shared_ptr<MethodStatistics<std::string>>> m =
+    static const std::map<std::string, std::shared_ptr<MethodStatistics<std::string>>,
+            std::less<> /* transparent comparator */> m =
         // copy elided initialization of map m.
         [](){
-            std::map<std::string, std::shared_ptr<MethodStatistics<std::string>>> m;
+            std::map<std::string, std::shared_ptr<MethodStatistics<std::string>>, std::less<>> m;
             addClassesToMap(
                     getStatisticsClassesForModule(METHOD_STATISTICS_MODULE_NAME_AUDIO_HIDL),
                     m);
             return m;
         }();
 
-    auto it = m.find({className.begin(), className.end()});
+    auto it = m.find(className);
     if (it == m.end()) return {};
     return it->second;
 }
diff --git a/media/utils/TimeCheck.cpp b/media/utils/TimeCheck.cpp
index 0848eb3..6823f4f 100644
--- a/media/utils/TimeCheck.cpp
+++ b/media/utils/TimeCheck.cpp
@@ -21,6 +21,7 @@
 #include <android-base/logging.h>
 #include <audio_utils/clock.h>
 #include <mediautils/EventLog.h>
+#include <mediautils/FixedString.h>
 #include <mediautils/MethodStatistics.h>
 #include <mediautils/TimeCheck.h>
 #include <utils/Log.h>
@@ -138,22 +139,24 @@
     return getTimeCheckThread().toString();
 }
 
-TimeCheck::TimeCheck(std::string tag, OnTimerFunc&& onTimer, uint32_t timeoutMs,
-        bool crashOnTimeout)
-    : mTimeCheckHandler(new TimeCheckHandler{
-            std::move(tag), std::move(onTimer), crashOnTimeout,
-            std::chrono::system_clock::now(), gettid()})
-    , mTimerHandle(timeoutMs == 0
+TimeCheck::TimeCheck(std::string_view tag, OnTimerFunc&& onTimer, Duration requestedTimeoutDuration,
+        Duration secondChanceDuration, bool crashOnTimeout)
+    : mTimeCheckHandler{ std::make_shared<TimeCheckHandler>(
+            tag, std::move(onTimer), crashOnTimeout, requestedTimeoutDuration,
+            secondChanceDuration, std::chrono::system_clock::now(), gettid()) }
+    , mTimerHandle(requestedTimeoutDuration.count() == 0
+              /* for TimeCheck we don't consider a non-zero secondChanceDuration here */
               ? getTimeCheckThread().trackTask(mTimeCheckHandler->tag)
               : getTimeCheckThread().scheduleTask(
                       mTimeCheckHandler->tag,
                       // Pass in all the arguments by value to this task for safety.
                       // The thread could call the callback before the constructor is finished.
                       // The destructor is not blocked on callback.
-                      [ timeCheckHandler = mTimeCheckHandler ] {
-                          timeCheckHandler->onTimeout();
+                      [ timeCheckHandler = mTimeCheckHandler ](TimerThread::Handle timerHandle) {
+                          timeCheckHandler->onTimeout(timerHandle);
                       },
-                      std::chrono::milliseconds(timeoutMs))) {}
+                      requestedTimeoutDuration,
+                      secondChanceDuration)) {}
 
 TimeCheck::~TimeCheck() {
     if (mTimeCheckHandler) {
@@ -161,23 +164,77 @@
     }
 }
 
+/* static */
+std::string TimeCheck::analyzeTimeouts(
+        float requestedTimeoutMs, float elapsedSteadyMs, float elapsedSystemMs) {
+    // Track any OS clock issues with suspend.
+    // It is possible that the elapsedSystemMs is much greater than elapsedSteadyMs if
+    // a suspend occurs; however, we always expect the timeout ms should always be slightly
+    // less than the elapsed steady ms regardless of whether a suspend occurs or not.
+
+    std::string s("Timeout ms ");
+    s.append(std::to_string(requestedTimeoutMs))
+        .append(" elapsed steady ms ").append(std::to_string(elapsedSteadyMs))
+        .append(" elapsed system ms ").append(std::to_string(elapsedSystemMs));
+
+    // Is there something unusual?
+    static constexpr float TOLERANCE_CONTEXT_SWITCH_MS = 200.f;
+
+    if (requestedTimeoutMs > elapsedSteadyMs || requestedTimeoutMs > elapsedSystemMs) {
+        s.append("\nError: early expiration - "
+                "requestedTimeoutMs should be less than elapsed time");
+    }
+
+    if (elapsedSteadyMs > elapsedSystemMs + TOLERANCE_CONTEXT_SWITCH_MS) {
+        s.append("\nWarning: steady time should not advance faster than system time");
+    }
+
+    // This has been found in suspend stress testing.
+    if (elapsedSteadyMs > requestedTimeoutMs + TOLERANCE_CONTEXT_SWITCH_MS) {
+        s.append("\nWarning: steady time significantly exceeds timeout "
+                "- possible thread stall or aborted suspend");
+    }
+
+    // This has been found in suspend stress testing.
+    if (elapsedSystemMs > requestedTimeoutMs + TOLERANCE_CONTEXT_SWITCH_MS) {
+        s.append("\nInformation: system time significantly exceeds timeout "
+                "- possible suspend");
+    }
+    return s;
+}
+
+// To avoid any potential race conditions, the timer handle
+// (expiration = clock steady start + timeout) is passed into the callback.
 void TimeCheck::TimeCheckHandler::onCancel(TimerThread::Handle timerHandle) const
 {
     if (TimeCheck::getTimeCheckThread().cancelTask(timerHandle) && onTimer) {
-        const std::chrono::system_clock::time_point endTime = std::chrono::system_clock::now();
-        onTimer(false /* timeout */,
-                std::chrono::duration_cast<std::chrono::duration<float, std::milli>>(
-                        endTime - startTime).count());
+        const std::chrono::steady_clock::time_point endSteadyTime =
+                std::chrono::steady_clock::now();
+        const float elapsedSteadyMs = std::chrono::duration_cast<FloatMs>(
+                endSteadyTime - timerHandle + timeoutDuration).count();
+        // send the elapsed steady time for statistics.
+        onTimer(false /* timeout */, elapsedSteadyMs);
     }
 }
 
-void TimeCheck::TimeCheckHandler::onTimeout() const
+// To avoid any potential race conditions, the timer handle
+// (expiration = clock steady start + timeout) is passed into the callback.
+void TimeCheck::TimeCheckHandler::onTimeout(TimerThread::Handle timerHandle) const
 {
-    const std::chrono::system_clock::time_point endTime = std::chrono::system_clock::now();
+    const std::chrono::steady_clock::time_point endSteadyTime = std::chrono::steady_clock::now();
+    const std::chrono::system_clock::time_point endSystemTime = std::chrono::system_clock::now();
+    // timerHandle incorporates the timeout
+    const float elapsedSteadyMs = std::chrono::duration_cast<FloatMs>(
+            endSteadyTime - (timerHandle - timeoutDuration)).count();
+    const float elapsedSystemMs = std::chrono::duration_cast<FloatMs>(
+            endSystemTime - startSystemTime).count();
+    const float requestedTimeoutMs = std::chrono::duration_cast<FloatMs>(
+            timeoutDuration).count();
+    const float secondChanceMs = std::chrono::duration_cast<FloatMs>(
+            secondChanceDuration).count();
+
     if (onTimer) {
-        onTimer(true /* timeout */,
-                std::chrono::duration_cast<std::chrono::duration<float, std::milli>>(
-                        endTime - startTime).count());
+        onTimer(true /* timeout */, elapsedSteadyMs);
     }
 
     if (!crashOnTimeout) return;
@@ -207,8 +264,10 @@
     // Create abort message string - caution: this can be very large.
     const std::string abortMessage = std::string("TimeCheck timeout for ")
             .append(tag)
-            .append(" scheduled ").append(formatTime(startTime))
+            .append(" scheduled ").append(formatTime(startSystemTime))
             .append(" on thread ").append(std::to_string(tid)).append("\n")
+            .append(analyzeTimeouts(requestedTimeoutMs + secondChanceMs,
+                    elapsedSteadyMs, elapsedSystemMs)).append("\n")
             .append(halPids).append("\n")
             .append(summary);
 
@@ -231,16 +290,16 @@
             mediautils::getStatisticsForClass(className);
     if (!statistics) return {}; // empty TimeCheck.
     return mediautils::TimeCheck(
-            std::string(className).append("::").append(methodName),
-            [ clazz = std::string(className), method = std::string(methodName),
+            FixedString62(className).append("::").append(methodName),
+            [ safeMethodName = FixedString30(methodName),
               stats = std::move(statistics) ]
             (bool timeout, float elapsedMs) {
                     if (timeout) {
                         ; // ignored, there is no timeout value.
                     } else {
-                        stats->event(method, elapsedMs);
+                        stats->event(safeMethodName.asStringView(), elapsedMs);
                     }
-            }, 0 /* timeoutMs */);
+            }, {} /* timeoutDuration */, {} /* secondChanceDuration */, false /* crashOnTimeout */);
 }
 
 }  // namespace android::mediautils
diff --git a/media/utils/TimerThread-test.cpp b/media/utils/TimerThread-test.cpp
index 93cd64c..9452c07 100644
--- a/media/utils/TimerThread-test.cpp
+++ b/media/utils/TimerThread-test.cpp
@@ -33,10 +33,28 @@
     return std::count(s.begin(), s.end(), c);
 }
 
-TEST(TimerThread, Basic) {
+
+// Split msec time between timeout and second chance time
+// This tests expiration times weighted between timeout and the second chance time.
+#define DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(msec, frac) \
+    std::chrono::milliseconds(int((msec) * (frac)) + 1), \
+    std::chrono::milliseconds(int((msec) * (1.f - (frac))))
+
+// The TimerThreadTest is parameterized on a fraction between 0.f and 1.f which
+// is how the total timeout time is split between the first timeout and the second chance time.
+//
+class TimerThreadTest : public ::testing::TestWithParam<float> {
+protected:
+
+static void testBasic() {
+    const auto frac = GetParam();
+
     std::atomic<bool> taskRan = false;
     TimerThread thread;
-    thread.scheduleTask("Basic", [&taskRan] { taskRan = true; }, 100ms);
+    TimerThread::Handle handle =
+            thread.scheduleTask("Basic", [&taskRan](TimerThread::Handle handle __unused) {
+                    taskRan = true; }, DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(100, frac));
+    ASSERT_TRUE(TimerThread::isTimeoutHandle(handle));
     std::this_thread::sleep_for(100ms - kJitter);
     ASSERT_FALSE(taskRan);
     std::this_thread::sleep_for(2 * kJitter);
@@ -44,11 +62,15 @@
     ASSERT_EQ(1, countChars(thread.retiredToString(), REQUEST_START));
 }
 
-TEST(TimerThread, Cancel) {
+static void testCancel() {
+    const auto frac = GetParam();
+
     std::atomic<bool> taskRan = false;
     TimerThread thread;
     TimerThread::Handle handle =
-            thread.scheduleTask("Cancel", [&taskRan] { taskRan = true; }, 100ms);
+            thread.scheduleTask("Cancel", [&taskRan](TimerThread::Handle handle __unused) {
+                    taskRan = true; }, DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(100, frac));
+    ASSERT_TRUE(TimerThread::isTimeoutHandle(handle));
     std::this_thread::sleep_for(100ms - kJitter);
     ASSERT_FALSE(taskRan);
     ASSERT_TRUE(thread.cancelTask(handle));
@@ -57,88 +79,87 @@
     ASSERT_EQ(1, countChars(thread.retiredToString(), REQUEST_START));
 }
 
-TEST(TimerThread, CancelAfterRun) {
+static void testCancelAfterRun() {
+    const auto frac = GetParam();
+
     std::atomic<bool> taskRan = false;
     TimerThread thread;
     TimerThread::Handle handle =
-            thread.scheduleTask("CancelAfterRun", [&taskRan] { taskRan = true; }, 100ms);
+            thread.scheduleTask("CancelAfterRun",
+                    [&taskRan](TimerThread::Handle handle __unused) {
+                            taskRan = true; },
+                            DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(100, frac));
+    ASSERT_TRUE(TimerThread::isTimeoutHandle(handle));
     std::this_thread::sleep_for(100ms + kJitter);
     ASSERT_TRUE(taskRan);
     ASSERT_FALSE(thread.cancelTask(handle));
     ASSERT_EQ(1, countChars(thread.retiredToString(), REQUEST_START));
 }
 
-TEST(TimerThread, MultipleTasks) {
+static void testMultipleTasks() {
+    const auto frac = GetParam();
+
     std::array<std::atomic<bool>, 6> taskRan{};
     TimerThread thread;
 
     auto startTime = std::chrono::steady_clock::now();
 
-    thread.scheduleTask("0", [&taskRan] { taskRan[0] = true; }, 300ms);
-    thread.scheduleTask("1", [&taskRan] { taskRan[1] = true; }, 100ms);
-    thread.scheduleTask("2", [&taskRan] { taskRan[2] = true; }, 200ms);
-    thread.scheduleTask("3", [&taskRan] { taskRan[3] = true; }, 400ms);
-    auto handle4 = thread.scheduleTask("4", [&taskRan] { taskRan[4] = true; }, 200ms);
-    thread.scheduleTask("5", [&taskRan] { taskRan[5] = true; }, 200ms);
+    thread.scheduleTask("0", [&taskRan](TimerThread::Handle handle __unused) {
+            taskRan[0] = true; }, DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(300, frac));
+    thread.scheduleTask("1", [&taskRan](TimerThread::Handle handle __unused) {
+            taskRan[1] = true; }, DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(100, frac));
+    thread.scheduleTask("2", [&taskRan](TimerThread::Handle handle __unused) {
+            taskRan[2] = true; }, DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(200, frac));
+    thread.scheduleTask("3", [&taskRan](TimerThread::Handle handle __unused) {
+            taskRan[3] = true; }, DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(400, frac));
+    auto handle4 = thread.scheduleTask("4", [&taskRan](TimerThread::Handle handle __unused) {
+            taskRan[4] = true; }, DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(200, frac));
+    thread.scheduleTask("5", [&taskRan](TimerThread::Handle handle __unused) {
+            taskRan[5] = true; }, DISTRIBUTE_TIMEOUT_SECONDCHANCE_MS_FRAC(200, frac));
 
     // 6 tasks pending
     ASSERT_EQ(6, countChars(thread.pendingToString(), REQUEST_START));
     // 0 tasks completed
     ASSERT_EQ(0, countChars(thread.retiredToString(), REQUEST_START));
 
+    // None of the tasks are expected to have finished at the start.
+    std::array<std::atomic<bool>, 6> expected{};
+
     // Task 1 should trigger around 100ms.
     std::this_thread::sleep_until(startTime + 100ms - kJitter);
-    ASSERT_FALSE(taskRan[0]);
-    ASSERT_FALSE(taskRan[1]);
-    ASSERT_FALSE(taskRan[2]);
-    ASSERT_FALSE(taskRan[3]);
-    ASSERT_FALSE(taskRan[4]);
-    ASSERT_FALSE(taskRan[5]);
+
+    ASSERT_EQ(expected, taskRan);
+
 
     std::this_thread::sleep_until(startTime + 100ms + kJitter);
-    ASSERT_FALSE(taskRan[0]);
-    ASSERT_TRUE(taskRan[1]);
-    ASSERT_FALSE(taskRan[2]);
-    ASSERT_FALSE(taskRan[3]);
-    ASSERT_FALSE(taskRan[4]);
-    ASSERT_FALSE(taskRan[5]);
+
+    expected[1] = true;
+    ASSERT_EQ(expected, taskRan);
 
     // Cancel task 4 before it gets a chance to run.
     thread.cancelTask(handle4);
 
     // Tasks 2 and 5 should trigger around 200ms.
     std::this_thread::sleep_until(startTime + 200ms - kJitter);
-    ASSERT_FALSE(taskRan[0]);
-    ASSERT_TRUE(taskRan[1]);
-    ASSERT_FALSE(taskRan[2]);
-    ASSERT_FALSE(taskRan[3]);
-    ASSERT_FALSE(taskRan[4]);
-    ASSERT_FALSE(taskRan[5]);
+
+    ASSERT_EQ(expected, taskRan);
+
 
     std::this_thread::sleep_until(startTime + 200ms + kJitter);
-    ASSERT_FALSE(taskRan[0]);
-    ASSERT_TRUE(taskRan[1]);
-    ASSERT_TRUE(taskRan[2]);
-    ASSERT_FALSE(taskRan[3]);
-    ASSERT_FALSE(taskRan[4]);
-    ASSERT_TRUE(taskRan[5]);
+
+    expected[2] = true;
+    expected[5] = true;
+    ASSERT_EQ(expected, taskRan);
 
     // Task 0 should trigger around 300ms.
     std::this_thread::sleep_until(startTime + 300ms - kJitter);
-    ASSERT_FALSE(taskRan[0]);
-    ASSERT_TRUE(taskRan[1]);
-    ASSERT_TRUE(taskRan[2]);
-    ASSERT_FALSE(taskRan[3]);
-    ASSERT_FALSE(taskRan[4]);
-    ASSERT_TRUE(taskRan[5]);
+
+    ASSERT_EQ(expected, taskRan);
 
     std::this_thread::sleep_until(startTime + 300ms + kJitter);
-    ASSERT_TRUE(taskRan[0]);
-    ASSERT_TRUE(taskRan[1]);
-    ASSERT_TRUE(taskRan[2]);
-    ASSERT_FALSE(taskRan[3]);
-    ASSERT_FALSE(taskRan[4]);
-    ASSERT_TRUE(taskRan[5]);
+
+    expected[0] = true;
+    ASSERT_EQ(expected, taskRan);
 
     // 1 task pending
     ASSERT_EQ(1, countChars(thread.pendingToString(), REQUEST_START));
@@ -147,23 +168,16 @@
 
     // Task 3 should trigger around 400ms.
     std::this_thread::sleep_until(startTime + 400ms - kJitter);
-    ASSERT_TRUE(taskRan[0]);
-    ASSERT_TRUE(taskRan[1]);
-    ASSERT_TRUE(taskRan[2]);
-    ASSERT_FALSE(taskRan[3]);
-    ASSERT_FALSE(taskRan[4]);
-    ASSERT_TRUE(taskRan[5]);
+
+    ASSERT_EQ(expected, taskRan);
 
     // 4 tasks ran and 1 cancelled
     ASSERT_EQ(4 + 1, countChars(thread.retiredToString(), REQUEST_START));
 
     std::this_thread::sleep_until(startTime + 400ms + kJitter);
-    ASSERT_TRUE(taskRan[0]);
-    ASSERT_TRUE(taskRan[1]);
-    ASSERT_TRUE(taskRan[2]);
-    ASSERT_TRUE(taskRan[3]);
-    ASSERT_FALSE(taskRan[4]);
-    ASSERT_TRUE(taskRan[5]);
+
+    expected[3] = true;
+    ASSERT_EQ(expected, taskRan);
 
     // 0 tasks pending
     ASSERT_EQ(0, countChars(thread.pendingToString(), REQUEST_START));
@@ -171,6 +185,30 @@
     ASSERT_EQ(5 + 1, countChars(thread.retiredToString(), REQUEST_START));
 }
 
+}; // class TimerThreadTest
+
+TEST_P(TimerThreadTest, Basic) {
+    testBasic();
+}
+
+TEST_P(TimerThreadTest, Cancel) {
+    testCancel();
+}
+
+TEST_P(TimerThreadTest, CancelAfterRun) {
+    testCancelAfterRun();
+}
+
+TEST_P(TimerThreadTest, MultipleTasks) {
+    testMultipleTasks();
+}
+
+INSTANTIATE_TEST_CASE_P(
+        TimerThread,
+        TimerThreadTest,
+        ::testing::Values(0.f, 0.5f, 1.f)
+        );
+
 TEST(TimerThread, TrackedTasks) {
     TimerThread thread;
 
@@ -178,6 +216,10 @@
     auto handle1 = thread.trackTask("1");
     auto handle2 = thread.trackTask("2");
 
+    ASSERT_TRUE(TimerThread::isNoTimeoutHandle(handle0));
+    ASSERT_TRUE(TimerThread::isNoTimeoutHandle(handle1));
+    ASSERT_TRUE(TimerThread::isNoTimeoutHandle(handle2));
+
     // 3 tasks pending
     ASSERT_EQ(3, countChars(thread.pendingToString(), REQUEST_START));
     // 0 tasks retired
@@ -201,6 +243,7 @@
 
     // Add another tracked task.
     auto handle3 = thread.trackTask("3");
+    ASSERT_TRUE(TimerThread::isNoTimeoutHandle(handle3));
 
     // 2 tasks pending
     ASSERT_EQ(2, countChars(thread.pendingToString(), REQUEST_START));
diff --git a/media/utils/TimerThread.cpp b/media/utils/TimerThread.cpp
index 6de6b13..5e58a3d 100644
--- a/media/utils/TimerThread.cpp
+++ b/media/utils/TimerThread.cpp
@@ -23,30 +23,35 @@
 
 #include <mediautils/MediaUtilsDelayed.h>
 #include <mediautils/TimerThread.h>
+#include <utils/Log.h>
 #include <utils/ThreadDefs.h>
 
+using namespace std::chrono_literals;
+
 namespace android::mediautils {
 
 extern std::string formatTime(std::chrono::system_clock::time_point t);
 extern std::string_view timeSuffix(std::string_view time1, std::string_view time2);
 
 TimerThread::Handle TimerThread::scheduleTask(
-        std::string tag, std::function<void()>&& func, std::chrono::milliseconds timeout) {
+        std::string_view tag, TimerCallback&& func,
+        Duration timeoutDuration, Duration secondChanceDuration) {
     const auto now = std::chrono::system_clock::now();
-    std::shared_ptr<const Request> request{
-            new Request{ now, now + timeout, gettid(), std::move(tag) }};
-    return mMonitorThread.add(std::move(request), std::move(func), timeout);
+    auto request = std::make_shared<const Request>(now, now +
+            std::chrono::duration_cast<std::chrono::system_clock::duration>(timeoutDuration),
+            secondChanceDuration, gettid(), tag);
+    return mMonitorThread.add(std::move(request), std::move(func), timeoutDuration);
 }
 
-TimerThread::Handle TimerThread::trackTask(std::string tag) {
+TimerThread::Handle TimerThread::trackTask(std::string_view tag) {
     const auto now = std::chrono::system_clock::now();
-    std::shared_ptr<const Request> request{
-            new Request{ now, now, gettid(), std::move(tag) }};
+    auto request = std::make_shared<const Request>(now, now,
+            Duration{} /* secondChanceDuration */, gettid(), tag);
     return mNoTimeoutMap.add(std::move(request));
 }
 
 bool TimerThread::cancelTask(Handle handle) {
-    std::shared_ptr<const Request> request = mNoTimeoutMap.isValidHandle(handle) ?
+    std::shared_ptr<const Request> request = isNoTimeoutHandle(handle) ?
              mNoTimeoutMap.remove(handle) : mMonitorThread.remove(handle);
     if (!request) return false;
     mRetiredQueue.add(std::move(request));
@@ -84,6 +89,8 @@
 
     return std::string("now ")
             .append(formatTime(std::chrono::system_clock::now()))
+            .append("\nsecondChanceCount ")
+            .append(std::to_string(mMonitorThread.getSecondChanceCount()))
             .append(analysisSummary)
             .append("\ntimeout [ ")
             .append(requestsToString(timeoutRequests))
@@ -106,10 +113,10 @@
 //
 /* static */
 bool TimerThread::isRequestFromHal(const std::shared_ptr<const Request>& request) {
-    const size_t hidlPos = request->tag.find("Hidl");
+    const size_t hidlPos = request->tag.asStringView().find("Hidl");
     if (hidlPos == std::string::npos) return false;
     // should be a separator afterwards Hidl which indicates the string was in the class.
-    const size_t separatorPos = request->tag.find("::", hidlPos);
+    const size_t separatorPos = request->tag.asStringView().find("::", hidlPos);
     return separatorPos != std::string::npos;
 }
 
@@ -127,12 +134,12 @@
     std::vector<std::shared_ptr<const Request>> pendingExact;
     std::vector<std::shared_ptr<const Request>> pendingPossible;
 
-    // We look at pending requests that were scheduled no later than kDuration
+    // We look at pending requests that were scheduled no later than kPendingDuration
     // after the timeout request. This prevents false matches with calls
     // that naturally block for a short period of time
     // such as HAL write() and read().
     //
-    auto constexpr kDuration = std::chrono::milliseconds(1000);
+    constexpr Duration kPendingDuration = 1000ms;
     for (const auto& pending : pendingRequests) {
         // If the pending tid is the same as timeout tid, problem identified.
         if (pending->tid == timeout->tid) {
@@ -141,7 +148,7 @@
         }
 
         // if the pending tid is scheduled within time limit
-        if (pending->scheduled - timeout->scheduled < kDuration) {
+        if (pending->scheduled - timeout->scheduled < kPendingDuration) {
             pendingPossible.emplace_back(pending);
         }
     }
@@ -241,15 +248,11 @@
     }
 }
 
-bool TimerThread::NoTimeoutMap::isValidHandle(Handle handle) const {
-    return handle > getIndexedHandle(mNoTimeoutRequests);
-}
-
 TimerThread::Handle TimerThread::NoTimeoutMap::add(std::shared_ptr<const Request> request) {
     std::lock_guard lg(mNTMutex);
     // A unique handle is obtained by mNoTimeoutRequests.fetch_add(1),
     // This need not be under a lock, but we do so anyhow.
-    const Handle handle = getIndexedHandle(mNoTimeoutRequests++);
+    const Handle handle = getUniqueHandle_l();
     mMap[handle] = request;
     return handle;
 }
@@ -271,16 +274,6 @@
     }
 }
 
-TimerThread::Handle TimerThread::MonitorThread::getUniqueHandle_l(
-        std::chrono::milliseconds timeout) {
-    // To avoid key collisions, advance by 1 tick until the key is unique.
-    auto deadline = std::chrono::steady_clock::now() + timeout;
-    for (; mMonitorRequests.find(deadline) != mMonitorRequests.end();
-         deadline += std::chrono::steady_clock::duration(1))
-        ;
-    return deadline;
-}
-
 TimerThread::MonitorThread::MonitorThread(RequestQueue& timeoutQueue)
         : mTimeoutQueue(timeoutQueue)
         , mThread([this] { threadFunc(); }) {
@@ -300,24 +293,78 @@
 void TimerThread::MonitorThread::threadFunc() {
     std::unique_lock _l(mMutex);
     while (!mShouldExit) {
+        Handle nextDeadline = INVALID_HANDLE;
+        Handle now = INVALID_HANDLE;
         if (!mMonitorRequests.empty()) {
-            Handle nextDeadline = mMonitorRequests.begin()->first;
-            if (nextDeadline < std::chrono::steady_clock::now()) {
+            nextDeadline = mMonitorRequests.begin()->first;
+            now = std::chrono::steady_clock::now();
+            if (nextDeadline < now) {
+                auto node = mMonitorRequests.extract(mMonitorRequests.begin());
                 // Deadline has expired, handle the request.
+                auto secondChanceDuration = node.mapped().first->secondChanceDuration;
+                if (secondChanceDuration.count() != 0) {
+                    // We now apply the second chance duration to find the clock
+                    // monotonic second deadline.  The unique key is then the
+                    // pair<second_deadline, first_deadline>.
+                    //
+                    // The second chance prevents a false timeout should there be
+                    // any clock monotonic advancement during suspend.
+                    auto newHandle = now + secondChanceDuration;
+                    ALOGD("%s: TimeCheck second chance applied for %s",
+                            __func__, node.mapped().first->tag.c_str()); // should be rare event.
+                    mSecondChanceRequests.emplace_hint(mSecondChanceRequests.end(),
+                            std::make_pair(newHandle, nextDeadline),
+                            std::move(node.mapped()));
+                    // increment second chance counter.
+                    mSecondChanceCount.fetch_add(1 /* arg */, std::memory_order_relaxed);
+                } else {
+                    {
+                        _l.unlock();
+                        // We add Request to retired queue early so that it can be dumped out.
+                        mTimeoutQueue.add(std::move(node.mapped().first));
+                        node.mapped().second(nextDeadline);
+                        // Caution: we don't hold lock when we call TimerCallback,
+                        // but this is the timeout case!  We will crash soon,
+                        // maybe before returning.
+                        // anything left over is released here outside lock.
+                    }
+                    // reacquire the lock - if something was added, we loop immediately to check.
+                    _l.lock();
+                }
+                // always process expiring monitor requests first.
+                continue;
+            }
+        }
+        // now process any second chance requests.
+        if (!mSecondChanceRequests.empty()) {
+            Handle secondDeadline = mSecondChanceRequests.begin()->first.first;
+            if (now == INVALID_HANDLE) now = std::chrono::steady_clock::now();
+            if (secondDeadline < now) {
+                auto node = mSecondChanceRequests.extract(mSecondChanceRequests.begin());
                 {
-                    auto node = mMonitorRequests.extract(mMonitorRequests.begin());
                     _l.unlock();
                     // We add Request to retired queue early so that it can be dumped out.
                     mTimeoutQueue.add(std::move(node.mapped().first));
-                    node.mapped().second(); // Caution: we don't hold lock here - but do we care?
-                                            // this is the timeout case!  We will crash soon,
-                                            // maybe before returning.
-                    // anything left over is released here outside lock.
+                    const Handle originalHandle = node.key().second;
+                    node.mapped().second(originalHandle);
+                    // Caution: we don't hold lock when we call TimerCallback.
+                    // This is benign issue - we permit concurrent operations
+                    // while in the callback to the MonitorQueue.
+                    //
+                    // Anything left over is released here outside lock.
                 }
                 // reacquire the lock - if something was added, we loop immediately to check.
                 _l.lock();
                 continue;
             }
+            // update the deadline.
+            if (nextDeadline == INVALID_HANDLE) {
+                nextDeadline = secondDeadline;
+            } else {
+                nextDeadline = std::min(nextDeadline, secondDeadline);
+            }
+        }
+        if (nextDeadline != INVALID_HANDLE) {
             mCond.wait_until(_l, nextDeadline);
         } else {
             mCond.wait(_l);
@@ -326,26 +373,39 @@
 }
 
 TimerThread::Handle TimerThread::MonitorThread::add(
-        std::shared_ptr<const Request> request, std::function<void()>&& func,
-        std::chrono::milliseconds timeout) {
+        std::shared_ptr<const Request> request, TimerCallback&& func, Duration timeout) {
     std::lock_guard _l(mMutex);
     const Handle handle = getUniqueHandle_l(timeout);
-    mMonitorRequests.emplace(handle, std::make_pair(std::move(request), std::move(func)));
+    mMonitorRequests.emplace_hint(mMonitorRequests.end(),
+            handle, std::make_pair(std::move(request), std::move(func)));
     mCond.notify_all();
     return handle;
 }
 
 std::shared_ptr<const TimerThread::Request> TimerThread::MonitorThread::remove(Handle handle) {
+    std::pair<std::shared_ptr<const Request>, TimerCallback> data;
     std::unique_lock ul(mMutex);
-    const auto it = mMonitorRequests.find(handle);
-    if (it == mMonitorRequests.end()) {
-        return {};
+    if (const auto it = mMonitorRequests.find(handle);
+        it != mMonitorRequests.end()) {
+        data = std::move(it->second);
+        mMonitorRequests.erase(it);
+        ul.unlock();  // manually release lock here so func (data.second)
+                      // is released outside of lock.
+        return data.first;  // request
     }
-    std::shared_ptr<const TimerThread::Request> request = std::move(it->second.first);
-    std::function<void()> func = std::move(it->second.second);
-    mMonitorRequests.erase(it);
-    ul.unlock();  // manually release lock here so func is released outside of lock.
-    return request;
+
+    // this check is O(N), but since the second chance requests are ordered
+    // in terms of earliest expiration time, we would expect better than average results.
+    for (auto it = mSecondChanceRequests.begin(); it != mSecondChanceRequests.end(); ++it) {
+        if (it->first.second == handle) {
+            data = std::move(it->second);
+            mSecondChanceRequests.erase(it);
+            ul.unlock();  // manually release lock here so func (data.second)
+                          // is released outside of lock.
+            return data.first; // request
+        }
+    }
+    return {};
 }
 
 void TimerThread::MonitorThread::copyRequests(
@@ -354,6 +414,13 @@
     for (const auto &[deadline, monitorpair] : mMonitorRequests) {
         requests.emplace_back(monitorpair.first);
     }
+    // we combine the second map with the first map - this is
+    // everything that is pending on the monitor thread.
+    // The second map will be older than the first map so this
+    // is in order.
+    for (const auto &[deadline, monitorpair] : mSecondChanceRequests) {
+        requests.emplace_back(monitorpair.first);
+    }
 }
 
 }  // namespace android::mediautils
diff --git a/media/utils/fuzzers/TimeCheckFuzz.cpp b/media/utils/fuzzers/TimeCheckFuzz.cpp
index 7966469..65b2885 100644
--- a/media/utils/fuzzers/TimeCheckFuzz.cpp
+++ b/media/utils/fuzzers/TimeCheckFuzz.cpp
@@ -48,7 +48,9 @@
     std::string name = data_provider.ConsumeRandomLengthString(kMaxStringLen);
 
     // 3. The constructor, which is fuzzed here:
-    android::mediautils::TimeCheck timeCheck(name.c_str(), {} /* onTimer */, timeoutMs);
+    android::mediautils::TimeCheck timeCheck(name.c_str(), {} /* onTimer */,
+            std::chrono::milliseconds(timeoutMs),
+            {} /* secondChanceDuration */, true /* crashOnTimeout */);
     // We will leave some buffer to avoid sleeping too long
     uint8_t sleep_amount_ms = data_provider.ConsumeIntegralInRange<uint8_t>(0, timeoutMs / 2);
 
diff --git a/media/utils/include/mediautils/FixedString.h b/media/utils/include/mediautils/FixedString.h
new file mode 100644
index 0000000..047aa82
--- /dev/null
+++ b/media/utils/include/mediautils/FixedString.h
@@ -0,0 +1,282 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <algorithm>
+#include <string>
+#include <string_view>
+
+namespace android::mediautils {
+
+/*
+ * FixedString is a stack allocatable string buffer that supports
+ * simple appending of other strings and string_views.
+ *
+ * It is designed for no-malloc operation when std::string
+ * small buffer optimization is insufficient.
+ *
+ * To keep code small, use asStringView() for operations on this.
+ *
+ * Notes:
+ * 1) Appending beyond the internal buffer size results in truncation.
+ *
+ * Alternatives:
+ * 1) If you want a sharable copy-on-write string implementation,
+ *    consider using the legacy android::String8().
+ * 2) Using std::string with a fixed stack allocator may suit your needs,
+ *    but exception avoidance is tricky.
+ * 3) Using C++20 ranges https://en.cppreference.com/w/cpp/ranges if you don't
+ *    need backing store.  Be careful about allocation with ranges.
+ *
+ * Good small sizes are multiples of 16 minus 2, e.g. 14, 30, 46, 62.
+ *
+ * Implementation Notes:
+ * 1) No iterators or [] for FixedString - please convert to std::string_view.
+ * 2) For small N (e.g. less than 62), consider a change to always zero fill and
+ *    potentially prevent always zero terminating (if one only does append).
+ *
+ * Possible arguments to create/append:
+ * 1) A FixedString.
+ * 2) A single char.
+ * 3) A char * pointer.
+ * 4) A std::string.
+ * 5) A std::string_view (or something convertible to it).
+ *
+ * Example:
+ *
+ * FixedString s1(std::string("a"));    // ctor
+ * s1 << "bc" << 'd' << '\n';           // streaming append
+ * s1 += "hello";                       // += append
+ * ASSERT_EQ(s1, "abcd\nhello");
+ */
+template <uint32_t N>
+struct FixedString
+{
+    // Find the best size type.
+    using strsize_t = std::conditional_t<(N > 255), uint32_t, uint8_t>;
+
+    // constructors
+    FixedString() { // override default
+        buffer_[0] = '\0';
+    }
+
+    FixedString(const FixedString& other) { // override default.
+        copyFrom<N>(other);
+    }
+
+    // The following constructor is not explicit to allow
+    // FixedString<8> s = "abcd";
+    template <typename ...Types>
+    FixedString(Types&&... args) {
+        append(std::forward<Types>(args)...);
+    }
+
+    // copy assign (copyFrom checks for equality and returns *this).
+    FixedString& operator=(const FixedString& other) { // override default.
+        return copyFrom<N>(other);
+    }
+
+    template <typename ...Types>
+    FixedString& operator=(Types&&... args) {
+        size_ = 0;
+        return append(std::forward<Types>(args)...);
+    }
+
+    // operator equals
+    bool operator==(const char *s) const {
+        return strncmp(c_str(), s, capacity() + 1) == 0;
+    }
+
+    bool operator==(std::string_view s) const {
+        return size() == s.size() && memcmp(data(), s.data(), size()) == 0;
+    }
+
+    // operator not-equals
+    template <typename T>
+    bool operator!=(const T& other) const {
+        return !operator==(other);
+    }
+
+    // operator +=
+    template <typename ...Types>
+    FixedString& operator+=(Types&&... args) {
+        return append(std::forward<Types>(args)...);
+    }
+
+    // conversion to std::string_view.
+    operator std::string_view() const {
+        return asStringView();
+    }
+
+    // basic observers
+    size_t buffer_offset() const { return offsetof(std::decay_t<decltype(*this)>, buffer_); }
+    static constexpr uint32_t capacity() { return N; }
+    uint32_t size() const { return size_; }
+    uint32_t remaining() const { return size_ >= N ? 0 : N - size_; }
+    bool empty() const { return size_ == 0; }
+    bool full() const { return size_ == N; }  // when full, possible truncation risk.
+    char * data() { return buffer_; }
+    const char * data() const { return buffer_; }
+    const char * c_str() const { return buffer_; }
+
+    inline std::string_view asStringView() const {
+        return { buffer_, static_cast<size_t>(size_) };
+    }
+    inline std::string asString() const {
+        return { buffer_, static_cast<size_t>(size_) };
+    }
+
+    void clear() { size_ = 0; buffer_[0] = 0; }
+
+    // Implementation of append - using templates
+    // to guarantee precedence in the presence of ambiguity.
+    //
+    // Consider C++20 template overloading through constraints and concepts.
+    template <typename T>
+    FixedString& append(const T& t) {
+        using decayT = std::decay_t<T>;
+        if constexpr (is_specialization_v<decayT, FixedString>) {
+            // A FixedString<U>
+            if (size_ == 0) {
+                // optimization to erase everything.
+                return copyFrom(t);
+            } else {
+                return appendStringView({t.data(), t.size()});
+            }
+        } else if constexpr(std::is_same_v<decayT, char>) {
+            if (size_ < N) {
+                buffer_[size_++] = t;
+                buffer_[size_] = '\0';
+            }
+            return *this;
+        } else if constexpr(std::is_same_v<decayT, char *>) {
+            // Some char* ptr.
+            return appendString(t);
+        } else if constexpr (std::is_convertible_v<decayT, std::string_view>) {
+            // std::string_view, std::string, or some other convertible type.
+            return appendStringView(t);
+        } else /* constexpr */ {
+            static_assert(dependent_false_v<T>, "non-matching append type");
+        }
+    }
+
+    FixedString& appendStringView(std::string_view s) {
+        uint32_t total = std::min(static_cast<size_t>(N - size_), s.size());
+        memcpy(buffer_ + size_, s.data(), total);
+        size_ += total;
+        buffer_[size_] = '\0';
+        return *this;
+    }
+
+    FixedString& appendString(const char *s) {
+        // strncpy zero pads to the end,
+        // strlcpy returns total expected length,
+        // we don't have strncpy_s in Bionic,
+        // so we write our own here.
+        while (size_ < N && *s != '\0') {
+            buffer_[size_++] = *s++;
+        }
+        buffer_[size_] = '\0';
+        return *this;
+    }
+
+    // Copy initialize the struct.
+    // Note: We are POD but customize the copying for acceleration
+    // of moving small strings embedded in a large buffers.
+    template <uint32_t U>
+    FixedString& copyFrom(const FixedString<U>& other) {
+        if ((void*)this != (void*)&other) { // not a self-assignment
+            if (other.size() == 0) {
+                size_ = 0;
+                buffer_[0] = '\0';
+                return *this;
+            }
+            constexpr size_t kSizeToCopyWhole = 64;
+            if constexpr (N == U &&
+                    sizeof(*this) == sizeof(other) &&
+                    sizeof(*this) <= kSizeToCopyWhole) {
+                // As we have the same str size type, we can just
+                // memcpy with fixed size, which can be easily optimized.
+                memcpy(static_cast<void*>(this), static_cast<const void*>(&other), sizeof(*this));
+                return *this;
+            }
+            if constexpr (std::is_same_v<strsize_t, typename FixedString<U>::strsize_t>) {
+                constexpr size_t kAlign = 8;  // align to a multiple of 8.
+                static_assert((kAlign & (kAlign - 1)) == 0); // power of 2.
+                // we check any alignment issues.
+                if (buffer_offset() == other.buffer_offset() && other.size() <= capacity()) {
+                    // improve on standard POD copying by reducing size.
+                    const size_t mincpy = buffer_offset() + other.size() + 1 /* nul */;
+                    const size_t maxcpy = std::min(sizeof(*this), sizeof(other));
+                    const size_t cpysize = std::min(mincpy + kAlign - 1 & ~(kAlign - 1), maxcpy);
+                    memcpy(static_cast<void*>(this), static_cast<const void*>(&other), cpysize);
+                    return *this;
+                }
+            }
+            size_ = std::min(other.size(), capacity());
+            memcpy(buffer_, other.data(), size_);
+            buffer_[size_] = '\0';  // zero terminate.
+        }
+        return *this;
+    }
+
+private:
+    //  Template helper methods
+
+    template <typename Test, template <uint32_t> class Ref>
+    struct is_specialization : std::false_type {};
+
+    template <template <uint32_t> class Ref, uint32_t UU>
+    struct is_specialization<Ref<UU>, Ref>: std::true_type {};
+
+    template <typename Test, template <uint32_t> class Ref>
+    static inline constexpr bool is_specialization_v = is_specialization<Test, Ref>::value;
+
+    // For static assert(false) we need a template version to avoid early failure.
+    template <typename T>
+    static inline constexpr bool dependent_false_v = false;
+
+    // POD variables
+    strsize_t size_ = 0;
+    char buffer_[N + 1 /* allow zero termination */];
+};
+
+// Stream operator syntactic sugar.
+// Example:
+// s << 'b' << "c" << "d" << '\n';
+template <uint32_t N, typename ...Types>
+FixedString<N>& operator<<(FixedString<N>& fs, Types&&... args) {
+    return fs.append(std::forward<Types>(args)...);
+}
+
+// We do not use a default size for fixed string as changing
+// the default size would lead to different behavior - we want the
+// size to be explicitly known.
+
+// FixedString62 of 62 chars fits in one typical cache line.
+using FixedString62 = FixedString<62>;
+
+// Slightly smaller
+using FixedString30 = FixedString<30>;
+
+// Since we have added copy and assignment optimizations,
+// we are no longer trivially assignable and copyable.
+// But we check standard layout here to prevent inclusion of unacceptable members or virtuals.
+static_assert(std::is_standard_layout_v<FixedString62>);
+static_assert(std::is_standard_layout_v<FixedString30>);
+
+}  // namespace android::mediautils
diff --git a/media/utils/include/mediautils/MethodStatistics.h b/media/utils/include/mediautils/MethodStatistics.h
index 700fbaa..6d7e990 100644
--- a/media/utils/include/mediautils/MethodStatistics.h
+++ b/media/utils/include/mediautils/MethodStatistics.h
@@ -55,15 +55,23 @@
     /**
      * Adds a method event, typically execution time in ms.
      */
-    void event(Code code, FloatType executeMs) {
+    template <typename C>
+    void event(C&& code, FloatType executeMs) {
         std::lock_guard lg(mLock);
-        mStatisticsMap[code].add(executeMs);
+        auto it = mStatisticsMap.lower_bound(code);
+        if (it != mStatisticsMap.end() && it->first == code) {
+            it->second.add(executeMs);
+        } else {
+            // StatsType ctor takes an optional array of data for initialization.
+            FloatType dataArray[1] = { executeMs };
+            mStatisticsMap.emplace_hint(it, std::forward<C>(code), dataArray);
+        }
     }
 
     /**
      * Returns the name for the method code.
      */
-    std::string getMethodForCode(Code code) const {
+    std::string getMethodForCode(const Code& code) const {
         auto it = mMethodMap.find(code);
         return it == mMethodMap.end() ? std::to_string((int)code) : it->second;
     }
@@ -71,7 +79,7 @@
     /**
      * Returns the number of times the method was invoked by event().
      */
-    size_t getMethodCount(Code code) const {
+    size_t getMethodCount(const Code& code) const {
         std::lock_guard lg(mLock);
         auto it = mStatisticsMap.find(code);
         return it == mStatisticsMap.end() ? 0 : it->second.getN();
@@ -80,7 +88,7 @@
     /**
      * Returns the statistics object for the method.
      */
-    StatsType getStatistics(Code code) const {
+    StatsType getStatistics(const Code& code) const {
         std::lock_guard lg(mLock);
         auto it = mStatisticsMap.find(code);
         return it == mStatisticsMap.end() ? StatsType{} : it->second;
@@ -107,9 +115,10 @@
     }
 
 private:
-    const std::map<Code, std::string> mMethodMap;
+    // Note: we use a transparent comparator std::less<> for heterogeneous key lookup.
+    const std::map<Code, std::string, std::less<>> mMethodMap;
     mutable std::mutex mLock;
-    std::map<Code, StatsType> mStatisticsMap GUARDED_BY(mLock);
+    std::map<Code, StatsType, std::less<>> mStatisticsMap GUARDED_BY(mLock);
 };
 
 // Managed Statistics support.
diff --git a/media/utils/include/mediautils/TimeCheck.h b/media/utils/include/mediautils/TimeCheck.h
index ef03aef..bdb5337 100644
--- a/media/utils/include/mediautils/TimeCheck.h
+++ b/media/utils/include/mediautils/TimeCheck.h
@@ -16,6 +16,7 @@
 
 #pragma once
 
+#include <chrono>
 #include <vector>
 
 #include <mediautils/TimerThread.h>
@@ -27,10 +28,33 @@
 
 class TimeCheck {
   public:
+
+    // Duration for TimeCheck is based on steady_clock, typically nanoseconds.
+    using Duration = std::chrono::steady_clock::duration;
+
+    // Duration for printing is in milliseconds, using float for additional precision.
+    using FloatMs = std::chrono::duration<float, std::milli>;
+
+    // OnTimerFunc is the callback function with 2 parameters.
+    //  bool timeout  (which is true when the TimeCheck object
+    //                 times out, false when the TimeCheck object is
+    //                 destroyed or leaves scope before the timer expires.)
+    //  float elapsedMs (the elapsed time to this event).
     using OnTimerFunc = std::function<void(bool /* timeout */, float /* elapsedMs */ )>;
 
     // The default timeout is chosen to be less than system server watchdog timeout
-    static constexpr uint32_t kDefaultTimeOutMs = 5000;
+    // Note: kDefaultTimeOutMs should be no less than 2 seconds, otherwise spurious timeouts
+    // may occur with system suspend.
+    static constexpr TimeCheck::Duration kDefaultTimeoutDuration = std::chrono::milliseconds(3000);
+
+    // Due to suspend abort not incrementing the monotonic clock,
+    // we allow another second chance timeout after the first timeout expires.
+    //
+    // The total timeout is therefore kDefaultTimeoutDuration + kDefaultSecondChanceDuration,
+    // and the result is more stable when the monotonic clock increments during suspend.
+    //
+    static constexpr TimeCheck::Duration kDefaultSecondChanceDuration =
+            std::chrono::milliseconds(2000);
 
     /**
      * TimeCheck is a RAII object which will notify a callback
@@ -44,24 +68,24 @@
      * the deallocation.
      *
      * \param tag       string associated with the TimeCheck object.
-     * \param onTimer   callback function with 2 parameters
-     *                      bool timeout  (which is true when the TimeCheck object
-     *                                    times out, false when the TimeCheck object is
-     *                                    destroyed or leaves scope before the timer expires.)
-     *                      float elapsedMs (the elapsed time to this event).
+     * \param onTimer   callback function with 2 parameters (described above in OnTimerFunc).
      *                  The callback when timeout is true will be called on a different thread.
      *                  This will cancel the callback on the destructor but is not guaranteed
      *                  to block for callback completion if it is already in progress
      *                  (for maximum concurrency and reduced deadlock potential), so use proper
      *                  lifetime analysis (e.g. shared or weak pointers).
-     * \param timeoutMs timeout in milliseconds.
+     * \param requestedTimeoutDuration timeout in milliseconds.
      *                  A zero timeout means no timeout is set -
      *                  the callback is called only when
      *                  the TimeCheck object is destroyed or leaves scope.
+     * \param secondChanceDuration additional milliseconds to wait if the first timeout expires.
+     *                  This is used to prevent false timeouts if the steady (monotonic)
+     *                  clock advances on aborted suspend.
      * \param crashOnTimeout true if the object issues an abort on timeout.
      */
-    explicit TimeCheck(std::string tag, OnTimerFunc&& onTimer = {},
-            uint32_t timeoutMs = kDefaultTimeOutMs, bool crashOnTimeout = true);
+    explicit TimeCheck(std::string_view tag, OnTimerFunc&& onTimer,
+            Duration requestedTimeoutDuration, Duration secondChanceDuration,
+            bool crashOnTimeout);
 
     TimeCheck() = default;
     // Remove copy constructors as there should only be one call to the destructor.
@@ -79,16 +103,36 @@
     // The usage here is const safe.
     class TimeCheckHandler {
     public:
-        const std::string tag;
+        template <typename S, typename F>
+        TimeCheckHandler(S&& _tag, F&& _onTimer, bool _crashOnTimeout,
+            Duration _timeoutDuration, Duration _secondChanceDuration,
+            std::chrono::system_clock::time_point _startSystemTime,
+            pid_t _tid)
+            : tag(std::forward<S>(_tag))
+            , onTimer(std::forward<F>(_onTimer))
+            , crashOnTimeout(_crashOnTimeout)
+            , timeoutDuration(_timeoutDuration)
+            , secondChanceDuration(_secondChanceDuration)
+            , startSystemTime(_startSystemTime)
+            , tid(_tid)
+            {}
+        const FixedString62 tag;
         const OnTimerFunc onTimer;
         const bool crashOnTimeout;
-        const std::chrono::system_clock::time_point startTime;
+        const Duration timeoutDuration;
+        const Duration secondChanceDuration;
+        const std::chrono::system_clock::time_point startSystemTime;
         const pid_t tid;
 
         void onCancel(TimerThread::Handle handle) const;
-        void onTimeout() const;
+        void onTimeout(TimerThread::Handle handle) const;
     };
 
+    // Returns a string that represents the timeout vs elapsed time,
+    // and diagnostics if there are any potential issues.
+    static std::string analyzeTimeouts(
+            float timeoutMs, float elapsedSteadyMs, float elapsedSystemMs);
+
     static TimerThread& getTimeCheckThread();
     static void accessAudioHalPids(std::vector<pid_t>* pids, bool update);
 
diff --git a/media/utils/include/mediautils/TimerThread.h b/media/utils/include/mediautils/TimerThread.h
index ffee602..c76fa7d 100644
--- a/media/utils/include/mediautils/TimerThread.h
+++ b/media/utils/include/mediautils/TimerThread.h
@@ -27,6 +27,8 @@
 
 #include <android-base/thread_annotations.h>
 
+#include <mediautils/FixedString.h>
+
 namespace android::mediautils {
 
 /**
@@ -34,19 +36,93 @@
  */
 class TimerThread {
   public:
-    // A Handle is a time_point that serves as a unique key.  It is ordered.
+    // A Handle is a time_point that serves as a unique key to access a queued
+    // request to the TimerThread.
     using Handle = std::chrono::steady_clock::time_point;
 
+    // Duration is based on steady_clock (typically nanoseconds)
+    // vs the system_clock duration (typically microseconds).
+    using Duration = std::chrono::steady_clock::duration;
+
     static inline constexpr Handle INVALID_HANDLE =
             std::chrono::steady_clock::time_point::min();
 
+    // Handle implementation details:
+    // A Handle represents the timer expiration time based on std::chrono::steady_clock
+    // (clock monotonic).  This Handle is computed as now() + timeout.
+    //
+    // The lsb of the Handle time_point is adjusted to indicate whether there is
+    // a timeout action (1) or not (0).
+    //
+
+    template <size_t COUNT>
+    static constexpr bool is_power_of_2_v = COUNT > 0 && (COUNT & (COUNT - 1)) == 0;
+
+    template <size_t COUNT>
+    static constexpr size_t mask_from_count_v = COUNT - 1;
+
+    static constexpr size_t HANDLE_TYPES = 2;
+    // HANDLE_TYPES must be a power of 2.
+    static_assert(is_power_of_2_v<HANDLE_TYPES>);
+
+    // The handle types
+    enum class HANDLE_TYPE : size_t {
+        NO_TIMEOUT = 0,
+        TIMEOUT = 1,
+    };
+
+    static constexpr size_t HANDLE_TYPE_MASK = mask_from_count_v<HANDLE_TYPES>;
+
+    template <typename T>
+    static constexpr auto enum_as_value(T x) {
+        return static_cast<std::underlying_type_t<T>>(x);
+    }
+
+    static inline bool isNoTimeoutHandle(Handle handle) {
+        return (handle.time_since_epoch().count() & HANDLE_TYPE_MASK) ==
+                enum_as_value(HANDLE_TYPE::NO_TIMEOUT);
+    }
+
+    static inline bool isTimeoutHandle(Handle handle) {
+        return (handle.time_since_epoch().count() & HANDLE_TYPE_MASK) ==
+                enum_as_value(HANDLE_TYPE::TIMEOUT);
+    }
+
+    // Returns a unique Handle that doesn't exist in the container.
+    template <size_t MAX_TYPED_HANDLES, size_t HANDLE_TYPE_AS_VALUE, typename C, typename T>
+    static Handle getUniqueHandleForHandleType_l(C container, T timeout) {
+        static_assert(MAX_TYPED_HANDLES > 0 && HANDLE_TYPE_AS_VALUE < MAX_TYPED_HANDLES
+                && is_power_of_2_v<MAX_TYPED_HANDLES>,
+                " handles must be power of two");
+
+        // Our initial handle is the deadline as computed from steady_clock.
+        auto deadline = std::chrono::steady_clock::now() + timeout;
+
+        // We adjust the lsbs by the minimum increment to have the correct
+        // HANDLE_TYPE in the least significant bits.
+        auto remainder = deadline.time_since_epoch().count() & HANDLE_TYPE_MASK;
+        size_t offset = HANDLE_TYPE_AS_VALUE > remainder ? HANDLE_TYPE_AS_VALUE - remainder :
+                     MAX_TYPED_HANDLES + HANDLE_TYPE_AS_VALUE - remainder;
+        deadline += std::chrono::steady_clock::duration(offset);
+
+        // To avoid key collisions, advance the handle by MAX_TYPED_HANDLES (the modulus factor)
+        // until the key is unique.
+        while (container.find(deadline) != container.end()) {
+            deadline += std::chrono::steady_clock::duration(MAX_TYPED_HANDLES);
+        }
+        return deadline;
+    }
+
+    // TimerCallback invoked on timeout or cancel.
+    using TimerCallback = std::function<void(Handle)>;
+
     /**
      * Schedules a task to be executed in the future (`timeout` duration from now).
      *
      * \param tag     string associated with the task.  This need not be unique,
      *                as the Handle returned is used for cancelling.
      * \param func    callback function that is invoked at the timeout.
-     * \param timeout timeout duration which is converted to milliseconds with at
+     * \param timeoutDuration timeout duration which is converted to milliseconds with at
      *                least 45 integer bits.
      *                A timeout of 0 (or negative) means the timer never expires
      *                so func() is never called. These tasks are stored internally
@@ -54,7 +130,8 @@
      * \returns       a handle that can be used for cancellation.
      */
     Handle scheduleTask(
-            std::string tag, std::function<void()>&& func, std::chrono::milliseconds timeout);
+            std::string_view tag, TimerCallback&& func,
+            Duration timeoutDuration, Duration secondChanceDuration);
 
     /**
      * Tracks a task that shows up on toString() until cancelled.
@@ -62,7 +139,7 @@
      * \param tag     string associated with the task.
      * \returns       a handle that can be used for cancellation.
      */
-    Handle trackTask(std::string tag);
+    Handle trackTask(std::string_view tag);
 
     /**
      * Cancels a task previously scheduled with scheduleTask()
@@ -128,14 +205,30 @@
   private:
     // To minimize movement of data, we pass around shared_ptrs to Requests.
     // These are allocated and deallocated outside of the lock.
+    // TODO(b/243839867) consider options to merge Request with the
+    // TimeCheck::TimeCheckHandler struct.
     struct Request {
+        Request(std::chrono::system_clock::time_point _scheduled,
+                std::chrono::system_clock::time_point _deadline,
+                Duration _secondChanceDuration,
+                pid_t _tid,
+                std::string_view _tag)
+            : scheduled(_scheduled)
+            , deadline(_deadline)
+            , secondChanceDuration(_secondChanceDuration)
+            , tid(_tid)
+            , tag(_tag)
+            {}
+
         const std::chrono::system_clock::time_point scheduled;
-        const std::chrono::system_clock::time_point deadline; // deadline := scheduled + timeout
+        const std::chrono::system_clock::time_point deadline; // deadline := scheduled
+                                                              // + timeoutDuration
+                                                              // + secondChanceDuration
                                                               // if deadline == scheduled, no
                                                               // timeout, task not executed.
+        Duration secondChanceDuration;
         const pid_t tid;
-        const std::string tag;
-
+        const FixedString62 tag;
         std::string toString() const;
     };
 
@@ -160,15 +253,17 @@
                 mRequestQueue GUARDED_BY(mRQMutex);
     };
 
-    // A storage map of tasks without timeouts.  There is no std::function<void()>
+    // A storage map of tasks without timeouts.  There is no TimerCallback
     // required, it just tracks the tasks with the tag, scheduled time and the tid.
     // These tasks show up on a pendingToString() until manually cancelled.
     class NoTimeoutMap {
-        // This a counter of the requests that have no timeout (timeout == 0).
-        std::atomic<size_t> mNoTimeoutRequests{};
-
         mutable std::mutex mNTMutex;
         std::map<Handle, std::shared_ptr<const Request>> mMap GUARDED_BY(mNTMutex);
+        Handle getUniqueHandle_l() REQUIRES(mNTMutex) {
+            return getUniqueHandleForHandleType_l<
+                    HANDLE_TYPES, enum_as_value(HANDLE_TYPE::NO_TIMEOUT)>(
+                mMap, Duration{} /* timeout */);
+        }
 
       public:
         bool isValidHandle(Handle handle) const; // lock free
@@ -182,14 +277,26 @@
     // call on timeout.
     // This class is thread-safe.
     class MonitorThread {
+        std::atomic<size_t> mSecondChanceCount{};
         mutable std::mutex mMutex;
-        mutable std::condition_variable mCond;
+        mutable std::condition_variable mCond GUARDED_BY(mMutex);
 
         // Ordered map of requests based on time of deadline.
         //
-        std::map<Handle, std::pair<std::shared_ptr<const Request>, std::function<void()>>>
+        std::map<Handle, std::pair<std::shared_ptr<const Request>, TimerCallback>>
                 mMonitorRequests GUARDED_BY(mMutex);
 
+        // Due to monotonic/steady clock inaccuracies during suspend,
+        // we allow an additional second chance waiting time to prevent
+        // false removal.
+
+        // This mSecondChanceRequests queue is almost always empty.
+        // Using a pair with the original handle allows lookup and keeps
+        // the Key unique.
+        std::map<std::pair<Handle /* new */, Handle /* original */>,
+                std::pair<std::shared_ptr<const Request>, TimerCallback>>
+                        mSecondChanceRequests GUARDED_BY(mMutex);
+
         RequestQueue& mTimeoutQueue; // locked internally, added to when request times out.
 
         // Worker thread variables
@@ -200,16 +307,23 @@
         std::thread mThread;
 
         void threadFunc();
-        Handle getUniqueHandle_l(std::chrono::milliseconds timeout) REQUIRES(mMutex);
+        Handle getUniqueHandle_l(Duration timeout) REQUIRES(mMutex) {
+            return getUniqueHandleForHandleType_l<
+                    HANDLE_TYPES, enum_as_value(HANDLE_TYPE::TIMEOUT)>(
+                mMonitorRequests, timeout);
+        }
 
       public:
         MonitorThread(RequestQueue &timeoutQueue);
         ~MonitorThread();
 
-        Handle add(std::shared_ptr<const Request> request, std::function<void()>&& func,
-                std::chrono::milliseconds timeout);
+        Handle add(std::shared_ptr<const Request> request, TimerCallback&& func,
+                Duration timeout);
         std::shared_ptr<const Request> remove(Handle handle);
         void copyRequests(std::vector<std::shared_ptr<const Request>>& requests) const;
+        size_t getSecondChanceCount() const {
+            return mSecondChanceCount.load(std::memory_order_relaxed);
+        }
     };
 
     // Analysis contains info deduced by analysisTimeout().
@@ -244,16 +358,6 @@
 
     std::vector<std::shared_ptr<const Request>> getPendingRequests() const;
 
-    // A no-timeout request is represented by a handles at the end of steady_clock time,
-    // counting down by the number of no timeout requests previously requested.
-    // We manage them on the NoTimeoutMap, but conceptually they could be scheduled
-    // on the MonitorThread because those time handles won't expire in
-    // the lifetime of the device.
-    static inline Handle getIndexedHandle(size_t index) {
-        return std::chrono::time_point<std::chrono::steady_clock>::max() -
-                    std::chrono::time_point<std::chrono::steady_clock>::duration(index);
-    }
-
     static constexpr size_t kRetiredQueueMax = 16;
     RequestQueue mRetiredQueue{kRetiredQueueMax};  // locked internally
 
diff --git a/media/utils/tests/Android.bp b/media/utils/tests/Android.bp
index 1024018..232cc4e 100644
--- a/media/utils/tests/Android.bp
+++ b/media/utils/tests/Android.bp
@@ -124,6 +124,27 @@
 }
 
 cc_test {
+    name: "mediautils_fixedstring_tests",
+
+    cflags: [
+        "-Wall",
+        "-Werror",
+        "-Wextra",
+    ],
+
+    shared_libs: [
+        "libaudioutils",
+        "liblog",
+        "libmediautils",
+        "libutils",
+    ],
+
+    srcs: [
+        "mediautils_fixedstring_tests.cpp",
+    ],
+}
+
+cc_test {
     name: "mediautils_scopedstatistics_tests",
 
     cflags: [
diff --git a/media/utils/tests/mediautils_fixedstring_tests.cpp b/media/utils/tests/mediautils_fixedstring_tests.cpp
new file mode 100644
index 0000000..7ab9a9f
--- /dev/null
+++ b/media/utils/tests/mediautils_fixedstring_tests.cpp
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "mediautils_fixedstring_tests"
+
+#include <mediautils/FixedString.h>
+
+#include <gtest/gtest.h>
+#include <utils/Log.h>
+
+using namespace android::mediautils;
+
+TEST(mediautils_fixedstring_tests, ctor) {
+    FixedString<8> s0("abcde");
+
+    ASSERT_FALSE(s0.empty());
+    ASSERT_EQ(8U, s0.capacity());
+
+    ASSERT_EQ(5U, s0.size());
+    ASSERT_EQ(3U, s0.remaining());
+    ASSERT_EQ(0, strcmp(s0.c_str(), "abcde"));
+
+    ASSERT_EQ(0, strcmp(s0.data(), "abcde"));
+
+    // overflow
+    FixedString<8> s1("abcdefghijk");
+    ASSERT_EQ(8U, s1.size());
+    ASSERT_TRUE(s1.full());
+    ASSERT_EQ(0U, s1.remaining());
+    ASSERT_EQ(0, strcmp(s1.c_str(), "abcdefgh"));
+
+    // overflow
+    FixedString<8> s2(std::string("abcdefghijk"));
+    ASSERT_TRUE(s2.full());
+
+    ASSERT_EQ(8U, s2.size());
+    ASSERT_EQ(0, strcmp(s2.c_str(), "abcdefgh"));
+
+    // complex
+    ASSERT_EQ(s1, s2);
+    ASSERT_EQ(FixedString<12>().append(s1), s2);
+    ASSERT_NE(s1, "bcd");
+
+    // string and stringview
+    ASSERT_EQ(s1.asString(), s1.asStringView());
+
+    FixedString30 s3;
+    s3 = std::string("abcd");
+    ASSERT_EQ(s3, "abcd");
+
+    s3.clear();
+    ASSERT_EQ(s3, "");
+    ASSERT_NE(s3, "abcd");
+    ASSERT_EQ(0U, s3.size());
+}
+
+TEST(mediautils_fixedstring_tests, append) {
+    FixedString<8> s0;
+    ASSERT_EQ(0U, s0.size());
+    ASSERT_EQ(0, strcmp(s0.c_str(), ""));
+    ASSERT_TRUE(s0.empty());
+    ASSERT_FALSE(s0.full());
+
+    s0.append("abc");
+    ASSERT_EQ(3U, s0.size());
+    ASSERT_EQ(0, strcmp(s0.c_str(), "abc"));
+
+    s0.append(std::string("d"));
+    ASSERT_EQ(4U, s0.size());
+    ASSERT_EQ(0, strcmp(s0.c_str(), "abcd"));
+
+    // overflow
+    s0.append("efghijk");
+    ASSERT_EQ(8U, s0.size());
+    ASSERT_EQ(0, strcmp(s0.c_str(), "abcdefgh"));
+    ASSERT_TRUE(s0.full());
+
+    // concatenated
+    ASSERT_EQ(FixedString62("abcd"),
+            FixedString<8>("ab").append("c").append(FixedString<8>("d")));
+    ASSERT_EQ(FixedString<12>("a").append(FixedString<12>("b")), "ab");
+}
+
+TEST(mediautils_fixedstring_tests, plus_equals) {
+    FixedString<8> s0;
+    ASSERT_EQ(0U, s0.size());
+    ASSERT_EQ(0, strcmp(s0.c_str(), ""));
+
+    s0 += "abc";
+    s0 += "def";
+    ASSERT_EQ(s0, "abcdef");
+}
+
+TEST(mediautils_fixedstring_tests, stream_operator) {
+    FixedString<8> s0('a');
+
+    s0 << 'b' << "c" << "d" << '\n';
+    ASSERT_EQ(s0, "abcd\n");
+}
+
+TEST(mediautils_fixedstring_tests, examples) {
+    FixedString30 s1(std::string("a"));
+    s1 << "bc" << 'd' << '\n';
+    s1 += "hello";
+
+    ASSERT_EQ(s1, "abcd\nhello");
+
+    FixedString30 s2;
+    for (const auto &c : s1.asStringView()) {
+        s2.append(c);
+    };
+    ASSERT_EQ(s1, s2);
+
+    FixedString30 s3(std::move(s1));
+}
+
+// Ensure type alias works fine as well.
+using FixedString1024 = FixedString<1024>;
+
+TEST(mediautils_fixedstring_tests, copy) {
+    FixedString1024 s0("abc");
+    FixedString62 s1(s0);
+
+    ASSERT_EQ(3U, s1.size());
+    ASSERT_EQ(0, strcmp(s1.c_str(), "abc"));
+    ASSERT_EQ(s0, s1);
+
+    FixedString<1024> s2(s1);
+    ASSERT_EQ(3U, s2.size());
+    ASSERT_EQ(0, strcmp(s2.c_str(), "abc"));
+    ASSERT_EQ(s2, "abc");
+    ASSERT_NE(s2, "def");
+    ASSERT_EQ(s2, std::string("abc"));
+    ASSERT_NE(s2, std::string("def"));
+    ASSERT_EQ(s1, s2);
+    ASSERT_EQ(s0, s2);
+    ASSERT_EQ(s2, FixedString62(FixedString1024("abc")));
+}
diff --git a/media/utils/tests/timecheck_tests.cpp b/media/utils/tests/timecheck_tests.cpp
index 6ebf44d..8236174 100644
--- a/media/utils/tests/timecheck_tests.cpp
+++ b/media/utils/tests/timecheck_tests.cpp
@@ -39,7 +39,7 @@
             timeoutRegistered = timeout;
             elapsedMsRegistered = elapsedMs;
             event = true;
-        }, 1000 /* msec */, false /* crash */);
+        }, 1000ms /* timeoutDuration */, {} /* secondChanceDuration */, false /* crash */);
     }
     ASSERT_TRUE(event);
     ASSERT_FALSE(timeoutRegistered);
@@ -58,7 +58,7 @@
             timeoutRegistered = timeout;
             elapsedMsRegistered = elapsedMs;
             event = true; // store-release, must be last.
-        }, 1 /* msec */, false /* crash */);
+        }, 1ms /* timeoutDuration */, {} /* secondChanceDuration */, false /* crash */);
         std::this_thread::sleep_for(100ms);
     }
     ASSERT_TRUE(event); // load-acquire, must be first.
@@ -69,4 +69,4 @@
 // Note: We do not test TimeCheck crash because TimeCheck is multithreaded and the
 // EXPECT_EXIT() signal catching is imperfect due to the gtest fork.
 
-} // namespace
\ No newline at end of file
+} // namespace
diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index 8ae06d0..4653f96 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -4602,7 +4602,9 @@
         } else {
             getIAudioFlingerStatistics().event(code, elapsedMs);
         }
-    });
+    }, mediautils::TimeCheck::kDefaultTimeoutDuration,
+    mediautils::TimeCheck::kDefaultSecondChanceDuration,
+    true /* crashOnTimeout */);
 
     // Make sure we connect to Audio Policy Service before calling into AudioFlinger:
     //  - AudioFlinger can call into Audio Policy Service with its global mutex held
diff --git a/services/audioflinger/Effects.cpp b/services/audioflinger/Effects.cpp
index e6d7cf7..24fe6f6 100644
--- a/services/audioflinger/Effects.cpp
+++ b/services/audioflinger/Effects.cpp
@@ -1790,7 +1790,7 @@
         } else {
             getIEffectStatistics().event(code, elapsedMs);
         }
-    }, 0 /* timeoutMs */);
+    }, {} /* timeoutDuration */, {} /* secondChanceDuration */, false /* crashOnTimeout */);
     return BnEffect::onTransact(code, data, reply, flags);
 }
 
diff --git a/services/audioflinger/ThreadMetrics.h b/services/audioflinger/ThreadMetrics.h
index 6526655..5493b3c 100644
--- a/services/audioflinger/ThreadMetrics.h
+++ b/services/audioflinger/ThreadMetrics.h
@@ -148,7 +148,14 @@
             item.set(AMEDIAMETRICS_PROP_CUMULATIVETIMENS, mCumulativeTimeNs)
                 .set(AMEDIAMETRICS_PROP_DEVICETIMENS, mDeviceTimeNs)
                 .set(AMEDIAMETRICS_PROP_EVENT, eventName)
-                .set(AMEDIAMETRICS_PROP_INTERVALCOUNT, (int32_t)mIntervalCount);
+                .set(AMEDIAMETRICS_PROP_INTERVALCOUNT, (int32_t)mIntervalCount)
+                // we set "last" device to indicate the device the group was
+                // associated with (because a createPatch which is logged in ThreadMetrics
+                // could have changed the device).
+                .set(mIsOut
+                        ? AMEDIAMETRICS_PROP_PREFIX_LAST AMEDIAMETRICS_PROP_OUTPUTDEVICES
+                        : AMEDIAMETRICS_PROP_PREFIX_LAST AMEDIAMETRICS_PROP_INPUTDEVICES,
+                        mDevices.c_str());
             if (mDeviceLatencyMs.getN() > 0) {
                 item.set(AMEDIAMETRICS_PROP_DEVICELATENCYMS, mDeviceLatencyMs.getMean());
             }
diff --git a/services/audiopolicy/common/managerdefinitions/src/AudioPolicyMix.cpp b/services/audiopolicy/common/managerdefinitions/src/AudioPolicyMix.cpp
index 551eab6..e142bef 100644
--- a/services/audiopolicy/common/managerdefinitions/src/AudioPolicyMix.cpp
+++ b/services/audiopolicy/common/managerdefinitions/src/AudioPolicyMix.cpp
@@ -232,7 +232,8 @@
 
         // Permit match only if requested format and mix format are PCM and can be format
         // adapted by the mixer, or are the same (compressed) format.
-        if (!((audio_is_linear_pcm(config.format) && audio_is_linear_pcm(mix->mFormat.format)) ||
+        if (!is_mix_loopback(mix->mRouteFlags) &&
+            !((audio_is_linear_pcm(config.format) && audio_is_linear_pcm(mix->mFormat.format)) ||
               (config.format == mix->mFormat.format)) &&
               config.format != AUDIO_CONFIG_BASE_INITIALIZER.format) {
             return MixMatchStatus::NO_MATCH;
diff --git a/services/audiopolicy/service/AudioPolicyService.cpp b/services/audiopolicy/service/AudioPolicyService.cpp
index 5f29d3f..dfdd351 100644
--- a/services/audiopolicy/service/AudioPolicyService.cpp
+++ b/services/audiopolicy/service/AudioPolicyService.cpp
@@ -272,6 +272,11 @@
         if (hasSpatializer) {
             mSpatializer = Spatializer::create(this);
         }
+        if (mSpatializer == nullptr) {
+            // No spatializer created, signal the reason: NO_INIT a failure, OK means intended.
+            const status_t createStatus = hasSpatializer ? NO_INIT : OK;
+            Spatializer::sendEmptyCreateSpatializerMetricWithStatus(createStatus);
+        }
     }
     AudioSystem::audioPolicyReady();
 }
@@ -516,7 +521,8 @@
 
 void AudioPolicyService::doOnCheckSpatializer()
 {
-    ALOGI("%s mSpatializer %p level %d", __func__, mSpatializer.get(), (int)mSpatializer->getLevel());
+    ALOGV("%s mSpatializer %p level %d",
+        __func__, mSpatializer.get(), (int)mSpatializer->getLevel());
 
     if (mSpatializer != nullptr) {
         // Note: mSpatializer != nullptr =>  mAudioPolicyManager != nullptr
@@ -1341,7 +1347,9 @@
         } else {
             getIAudioPolicyServiceStatistics().event(code, elapsedMs);
         }
-    });
+    }, mediautils::TimeCheck::kDefaultTimeoutDuration,
+    mediautils::TimeCheck::kDefaultSecondChanceDuration,
+    true /* crashOnTimeout */);
 
     switch (code) {
         case SHELL_COMMAND_TRANSACTION: {
diff --git a/services/audiopolicy/service/Spatializer.cpp b/services/audiopolicy/service/Spatializer.cpp
index 7755d22..9c989ce 100644
--- a/services/audiopolicy/service/Spatializer.cpp
+++ b/services/audiopolicy/service/Spatializer.cpp
@@ -59,11 +59,13 @@
        if (!_tmp.ok()) return aidl_utils::binderStatusFromStatusT(_tmp.error()); \
        std::move(_tmp.value()); })
 
-audio_channel_mask_t getMaxChannelMask(std::vector<audio_channel_mask_t> masks) {
+static audio_channel_mask_t getMaxChannelMask(
+        const std::vector<audio_channel_mask_t>& masks, size_t channelLimit = SIZE_MAX) {
     uint32_t maxCount = 0;
     audio_channel_mask_t maxMask = AUDIO_CHANNEL_NONE;
     for (auto mask : masks) {
         const size_t count = audio_channel_count_from_out_mask(mask);
+        if (count > channelLimit) continue;  // ignore masks greater than channelLimit
         if (count > maxCount) {
             maxMask = mask;
             maxCount = count;
@@ -175,13 +177,13 @@
 // ---------------------------------------------------------------------------
 
 // Convert recorded sensor data to string with level indentation.
-std::string Spatializer::HeadToStagePoseRecorder::toString_l(unsigned level) const {
+std::string Spatializer::HeadToStagePoseRecorder::toString(unsigned level) const {
     std::string prefixSpace(level, ' ');
     return mPoseRecordLog.dumpToString((prefixSpace + " ").c_str(), Spatializer::mMaxLocalLogLine);
 }
 
 // Compute sensor data, record into local log when it is time.
-void Spatializer::HeadToStagePoseRecorder::record_l(const std::vector<float>& headToStage) {
+void Spatializer::HeadToStagePoseRecorder::record(const std::vector<float>& headToStage) {
     if (headToStage.size() != mPoseVectorSize) return;
 
     if (mNumOfSampleSinceLastRecord++ == 0) {
@@ -191,12 +193,12 @@
     if (shouldRecordLog()) {
         poseSumToAverage();
         mPoseRecordLog.log(
-                "mean: %s, min: %s, max %s, calculated %d samples",
+                "mean: %s, min: %s, max %s, calculated %d samples in %0.4f second(s)",
                 Spatializer::toString<double>(mPoseRadianSum, true /* radianToDegree */).c_str(),
                 Spatializer::toString<float>(mMinPoseAngle, true /* radianToDegree */).c_str(),
                 Spatializer::toString<float>(mMaxPoseAngle, true /* radianToDegree */).c_str(),
-                mNumOfSampleSinceLastRecord);
-        resetRecord(headToStage);
+                mNumOfSampleSinceLastRecord, mNumOfSecondsSinceLastRecord.count());
+        resetRecord();
     }
     // update stream average.
     for (int i = 0; i < mPoseVectorSize; i++) {
@@ -238,9 +240,12 @@
         spatializer = new Spatializer(descriptors[0], callback);
         if (spatializer->loadEngineConfiguration(effect) != NO_ERROR) {
             spatializer.clear();
+            ALOGW("%s loadEngine error: %d  effect Id %" PRId64,
+                    __func__, status, effect ? effect->effectId() : 0);
+        } else {
+            spatializer->mLocalLog.log("%s with effect Id %" PRId64, __func__,
+                                       effect ? effect->effectId() : 0);
         }
-        spatializer->mLocalLog.log("%s with effect Id %" PRId64, __func__,
-                                   effect ? effect->effectId() : 0);
     }
 
     return spatializer;
@@ -274,6 +279,16 @@
     mHandler.clear();
 }
 
+static std::string channelMaskVectorToString(
+        const std::vector<audio_channel_mask_t>& masks) {
+    std::stringstream ss;
+    for (const auto &mask : masks) {
+        if (ss.tellp() != 0) ss << "|";
+        ss << mask;
+    }
+    return ss.str();
+}
+
 status_t Spatializer::loadEngineConfiguration(sp<EffectHalInterface> effect) {
     ALOGV("%s", __func__);
 
@@ -363,7 +378,7 @@
     }
     mediametrics::LogItem(mMetricsId)
         .set(AMEDIAMETRICS_PROP_EVENT, AMEDIAMETRICS_PROP_EVENT_VALUE_CREATE)
-        .set(AMEDIAMETRICS_PROP_CHANNELMASK, (int32_t)getMaxChannelMask(mChannelMasks))
+        .set(AMEDIAMETRICS_PROP_CHANNELMASKS, channelMaskVectorToString(mChannelMasks))
         .set(AMEDIAMETRICS_PROP_LEVELS, aidl_utils::enumsToString(mLevels))
         .set(AMEDIAMETRICS_PROP_MODES, aidl_utils::enumsToString(mSpatializationModes))
         .set(AMEDIAMETRICS_PROP_HEADTRACKINGMODES, aidl_utils::enumsToString(mHeadTrackingModes))
@@ -372,12 +387,24 @@
     return NO_ERROR;
 }
 
+/* static */
+void Spatializer::sendEmptyCreateSpatializerMetricWithStatus(status_t status) {
+    mediametrics::LogItem(kDefaultMetricsId)
+        .set(AMEDIAMETRICS_PROP_EVENT, AMEDIAMETRICS_PROP_EVENT_VALUE_CREATE)
+        .set(AMEDIAMETRICS_PROP_CHANNELMASKS, "")
+        .set(AMEDIAMETRICS_PROP_LEVELS, "")
+        .set(AMEDIAMETRICS_PROP_MODES, "")
+        .set(AMEDIAMETRICS_PROP_HEADTRACKINGMODES, "")
+        .set(AMEDIAMETRICS_PROP_STATUS, (int32_t)status)
+        .record();
+}
+
 /** Gets the channel mask, sampling rate and format set for the spatializer input. */
 audio_config_base_t Spatializer::getAudioInConfig() const {
     std::lock_guard lock(mLock);
     audio_config_base_t config = AUDIO_CONFIG_BASE_INITIALIZER;
     // For now use highest supported channel count
-    config.channel_mask = getMaxChannelMask(mChannelMasks);
+    config.channel_mask = getMaxChannelMask(mChannelMasks, FCC_LIMIT);
     return config;
 }
 
@@ -388,6 +415,17 @@
         return BAD_VALUE;
     }
 
+    if (mSpatializerCallback != nullptr) {
+        if (IInterface::asBinder(callback) == IInterface::asBinder(mSpatializerCallback)) {
+            ALOGW("%s: Registering callback %p again",
+                __func__, mSpatializerCallback.get());
+            return NO_ERROR;
+        }
+        ALOGE("%s: Already one client registered with callback %p",
+            __func__, mSpatializerCallback.get());
+        return INVALID_OPERATION;
+    }
+
     sp<IBinder> binder = IInterface::asBinder(callback);
     status_t status = binder->linkToDeath(this);
     if (status == NO_ERROR) {
@@ -541,7 +579,7 @@
     }
     std::lock_guard lock(mLock);
     if (mPoseController != nullptr) {
-        mLocalLog.log("%s with %s", __func__, toString<float>(screenToStage).c_str());
+        mLocalLog.log("%s with screenToStage %s", __func__, toString<float>(screenToStage).c_str());
         mPoseController->setScreenToStagePose(maybePose.value());
     }
     return Status::ok();
@@ -711,7 +749,8 @@
         callback = mHeadTrackingCallback;
         if (mEngine != nullptr) {
             setEffectParameter_l(SPATIALIZER_PARAM_HEAD_TO_STAGE, headToStage);
-            mPoseRecorder.record_l(headToStage);
+            mPoseRecorder.record(headToStage);
+            mPoseDurableRecorder.record(headToStage);
         }
     }
 
@@ -721,11 +760,9 @@
 }
 
 void Spatializer::onActualModeChange(HeadTrackingMode mode) {
-    std::string modeStr = SpatializerPoseController::toString(mode);
+    std::string modeStr = media::toString(mode);
     ALOGV("%s(%s)", __func__, modeStr.c_str());
-    mLocalLog.log("%s with %s", __func__, modeStr.c_str());
-    sp<AMessage> msg =
-            new AMessage(EngineCallbackHandler::kWhatOnActualModeChange, mHandler);
+    sp<AMessage> msg = new AMessage(EngineCallbackHandler::kWhatOnActualModeChange, mHandler);
     msg->setInt32(EngineCallbackHandler::kModeKey, static_cast<int>(mode));
     msg->post();
 }
@@ -759,8 +796,7 @@
                                  std::vector<SpatializerHeadTrackingMode>{spatializerMode});
         }
         callback = mHeadTrackingCallback;
-        mLocalLog.log("%s: %s, spatializerMode %s", __func__,
-                      SpatializerPoseController::toString(mode).c_str(),
+        mLocalLog.log("%s: %s, spatializerMode %s", __func__, media::toString(mode).c_str(),
                       media::toString(spatializerMode).c_str());
     }
     if (callback != nullptr) {
@@ -998,7 +1034,7 @@
         base::StringAppendF(&ss, " %s", media::toString(mode).c_str());
     }
     base::StringAppendF(&ss, "], Desired: %s, Actual %s\n",
-                        SpatializerPoseController::toString(mDesiredHeadTrackingMode).c_str(),
+                        media::toString(mDesiredHeadTrackingMode).c_str(),
                         media::toString(mActualHeadTrackingMode).c_str());
 
     base::StringAppendF(&ss, "%smSpatializationModes: [", prefixSpace.c_str());
@@ -1026,12 +1062,17 @@
 
     ss.append(prefixSpace + "CommandLog:\n");
     ss += mLocalLog.dumpToString((prefixSpace + " ").c_str(), mMaxLocalLogLine);
-    ss.append(prefixSpace + "SensorLog:\n");
-    ss += mPoseRecorder.toString_l(level + 1);
 
     // PostController dump.
     if (mPoseController != nullptr) {
         ss += mPoseController->toString(level + 1);
+        ss.append(prefixSpace +
+                  "Sensor data format - [rx, ry, rz, vx, vy, vz] (units-degree, "
+                  "r-transform, v-angular velocity, x-pitch, y-roll, z-yaw):\n");
+        ss.append(prefixSpace + " PerMinuteHistory:\n");
+        ss += mPoseDurableRecorder.toString(level + 1);
+        ss.append(prefixSpace + " PerSecondHistory:\n");
+        ss += mPoseRecorder.toString(level + 1);
     } else {
         ss.append(prefixSpace).append("SpatializerPoseController not exist\n");
     }
diff --git a/services/audiopolicy/service/Spatializer.h b/services/audiopolicy/service/Spatializer.h
index df2b215..2687b5c 100644
--- a/services/audiopolicy/service/Spatializer.h
+++ b/services/audiopolicy/service/Spatializer.h
@@ -184,18 +184,25 @@
         }
 
         std::string ss = "[";
-        for (const auto& f : vec) {
+        for (auto f = vec.begin(); f != vec.end(); ++f) {
+            if (f != vec.begin()) {
+                ss .append(", ");
+            }
             if (radianToDegree) {
-                base::StringAppendF(&ss, "%0.2f, ",
-                                    HeadToStagePoseRecorder::getDegreeWithRadian(f));
+                base::StringAppendF(&ss, "%0.2f", HeadToStagePoseRecorder::getDegreeWithRadian(*f));
             } else {
-                base::StringAppendF(&ss, "%f, ", f);
+                base::StringAppendF(&ss, "%f", *f);
             }
         }
-        ss.replace(ss.end() - 2, ss.end(), "]");
+        ss.append("]");
         return ss;
     };
 
+    // If the Spatializer is not created, we send the status for metrics purposes.
+    // OK:      Spatializer not expected to be created.
+    // NO_INIT: Spatializer creation failed.
+    static void sendEmptyCreateSpatializerMetricWithStatus(status_t status);
+
 private:
     Spatializer(effect_descriptor_t engineDescriptor,
                      SpatializerPolicyCallback *callback);
@@ -349,7 +356,9 @@
     SpatializerPolicyCallback* const mPolicyCallback;
 
     /** Currently there is only one version of the spatializer running */
-    const std::string mMetricsId = AMEDIAMETRICS_KEY_PREFIX_AUDIO_SPATIALIZER "0";
+    static constexpr const char* kDefaultMetricsId =
+            AMEDIAMETRICS_KEY_PREFIX_AUDIO_SPATIALIZER "0";
+    const std::string mMetricsId = kDefaultMetricsId;
 
     /** Mutex protecting internal state */
     mutable std::mutex mLock;
@@ -413,18 +422,23 @@
     /**
      * @brief Calculate and record sensor data.
      * Dump to local log with max/average pose angle every mPoseRecordThreshold.
-     * TODO: log azimuth/elevation angles obtained for debugging actual orientation.
      */
     class HeadToStagePoseRecorder {
       public:
+        HeadToStagePoseRecorder(std::chrono::duration<double> threshold, int maxLogLine)
+            : mPoseRecordThreshold(threshold), mPoseRecordLog(maxLogLine) {
+            resetRecord();
+        }
+
         /** Convert recorded sensor data to string with level indentation */
-        std::string toString_l(unsigned level) const;
+        std::string toString(unsigned level) const;
+
         /**
          * @brief Calculate sensor data, record into local log when it is time.
          *
          * @param headToStage The vector from Pose3f::toVector().
          */
-        void record_l(const std::vector<float>& headToStage);
+        void record(const std::vector<float>& headToStage);
 
         static constexpr float getDegreeWithRadian(const float radian) {
             float radianToDegreeRatio = (180 / PI);
@@ -435,11 +449,11 @@
         static constexpr float PI = M_PI;
         /**
          * Pose recorder time threshold to record sensor data in local log.
-         * Sensor data will be recorded at least every mPoseRecordThreshold.
+         * Sensor data will be recorded into log at least every mPoseRecordThreshold.
          */
-        // TODO: add another history log to record longer period of sensor data.
-        static constexpr std::chrono::duration<double> mPoseRecordThreshold =
-                std::chrono::seconds(1);
+        std::chrono::duration<double> mPoseRecordThreshold;
+        // Number of seconds pass since last record.
+        std::chrono::duration<double> mNumOfSecondsSinceLastRecord;
         /**
          * According to frameworks/av/media/libheadtracking/include/media/Pose.h
          * "The vector will have exactly 6 elements, where the first three are a translation vector
@@ -450,8 +464,6 @@
          * Timestamp of last sensor data record in local log.
          */
         std::chrono::time_point<std::chrono::steady_clock> mFirstSampleTimestamp;
-        // Last pose recorded, vector obtained from Pose3f::toVector().
-        std::vector<float> mLastPoseRecorded{mPoseVectorSize};
         /**
          * Number of sensor samples received since last record, sample rate is ~100Hz which produce
          * ~6k samples/minute.
@@ -461,24 +473,24 @@
          * mNumOfSampleSinceLastRecord to get arithmetic mean. Largest possible value: 2PI * 100Hz *
          * mPoseRecordThreshold.
          */
-        std::vector<double> mPoseRadianSum{mPoseVectorSize};
-        std::vector<float> mMaxPoseAngle{mPoseVectorSize};
-        std::vector<float> mMinPoseAngle{mPoseVectorSize};
+        std::vector<double> mPoseRadianSum;
+        std::vector<float> mMaxPoseAngle;
+        std::vector<float> mMinPoseAngle;
         // Local log for history sensor data.
         SimpleLog mPoseRecordLog{mMaxLocalLogLine};
 
-        bool shouldRecordLog() const {
-            return std::chrono::duration_cast<std::chrono::seconds>(
-                           std::chrono::steady_clock::now() - mFirstSampleTimestamp) >=
-                   mPoseRecordThreshold;
+        bool shouldRecordLog() {
+            mNumOfSecondsSinceLastRecord = std::chrono::duration_cast<std::chrono::seconds>(
+                    std::chrono::steady_clock::now() - mFirstSampleTimestamp);
+            return mNumOfSecondsSinceLastRecord >= mPoseRecordThreshold;
         }
 
-        void resetRecord(const std::vector<float>& headToStage) {
+        void resetRecord() {
             mPoseRadianSum.assign(mPoseVectorSize, 0);
-            mMaxPoseAngle.assign(mPoseVectorSize, 0);
-            mMinPoseAngle.assign(mPoseVectorSize, 0);
+            mMaxPoseAngle.assign(mPoseVectorSize, -PI);
+            mMinPoseAngle.assign(mPoseVectorSize, PI);
             mNumOfSampleSinceLastRecord = 0;
-            mLastPoseRecorded = headToStage;
+            mNumOfSecondsSinceLastRecord = std::chrono::seconds(0);
         }
 
         // Add each sample to sum and only calculate when record.
@@ -490,7 +502,13 @@
             }
         }
     };  // HeadToStagePoseRecorder
-    HeadToStagePoseRecorder mPoseRecorder;
+
+    // Record one log line per second (up to mMaxLocalLogLine) to capture most recent sensor data.
+    HeadToStagePoseRecorder mPoseRecorder GUARDED_BY(mLock) =
+            HeadToStagePoseRecorder(std::chrono::seconds(1), mMaxLocalLogLine);
+    // Record one log line per minute (up to mMaxLocalLogLine) to capture durable sensor data.
+    HeadToStagePoseRecorder mPoseDurableRecorder GUARDED_BY(mLock) =
+            HeadToStagePoseRecorder(std::chrono::minutes(1), mMaxLocalLogLine);
 };  // Spatializer
 
 }; // namespace android
diff --git a/services/audiopolicy/service/SpatializerPoseController.cpp b/services/audiopolicy/service/SpatializerPoseController.cpp
index e012a0b..72dba3d 100644
--- a/services/audiopolicy/service/SpatializerPoseController.cpp
+++ b/services/audiopolicy/service/SpatializerPoseController.cpp
@@ -43,7 +43,7 @@
 constexpr float kMaxTranslationalVelocity = 2;
 
 // This is how fast, in rad/s, we allow rotation angle to shift during rate-limiting.
-constexpr float kMaxRotationalVelocity = 8;
+constexpr float kMaxRotationalVelocity = 0.8f;
 
 // This is how far into the future we predict the head pose, using linear extrapolation based on
 // twist (velocity). It should be set to a value that matches the characteristic durations of moving
@@ -52,7 +52,9 @@
 constexpr auto kPredictionDuration = 50ms;
 
 // After not getting a pose sample for this long, we would treat the measurement as stale.
-constexpr auto kFreshnessTimeout = 50ms;
+// The max connection interval is 50ms, and HT sensor event interval can differ depending on the
+// sampling rate, scheduling, sensor eventQ FIFO etc. 120 (2 * 50 + 20) ms seems reasonable for now.
+constexpr auto kFreshnessTimeout = 120ms;
 
 // Auto-recenter kicks in after the head has been still for this long.
 constexpr auto kAutoRecenterWindowDuration = 6s;
@@ -65,13 +67,13 @@
 
 // Screen is considered to be unstable (not still) if it has moved significantly within the last
 // time window of this duration.
-constexpr auto kScreenStillnessWindowDuration = 3s;
+constexpr auto kScreenStillnessWindowDuration = 750ms;
 
 // Screen is considered to have moved significantly if translated by this much (in meter, approx).
 constexpr float kScreenStillnessTranslationThreshold = 0.1f;
 
 // Screen is considered to have moved significantly if rotated by this much (in radians, approx).
-constexpr float kScreenStillnessRotationThreshold = 7.0f / 180 * M_PI;
+constexpr float kScreenStillnessRotationThreshold = 15.0f / 180 * M_PI;
 
 // Time units for system clock ticks. This is what the Sensor Framework timestamps represent and
 // what we use for pose filtering.
@@ -310,14 +312,14 @@
     }
 
     ss += prefixSpace;
-    if (mHeadSensor == media::SensorPoseProvider::INVALID_HANDLE) {
-        ss.append("HeadSensor: INVALID\n");
+    if (mHeadSensor == INVALID_SENSOR) {
+        ss += "HeadSensor: INVALID\n";
     } else {
         base::StringAppendF(&ss, "HeadSensor: 0x%08x\n", mHeadSensor);
     }
 
     ss += prefixSpace;
-    if (mScreenSensor == media::SensorPoseProvider::INVALID_HANDLE) {
+    if (mScreenSensor == INVALID_SENSOR) {
         ss += "ScreenSensor: INVALID\n";
     } else {
         base::StringAppendF(&ss, "ScreenSensor: 0x%08x\n", mScreenSensor);
@@ -325,7 +327,7 @@
 
     ss += prefixSpace;
     if (mActualMode.has_value()) {
-        base::StringAppendF(&ss, "ActualMode: %s", toString(mActualMode.value()).c_str());
+        base::StringAppendF(&ss, "ActualMode: %s\n", media::toString(mActualMode.value()).c_str());
     } else {
         ss += "ActualMode NOTEXIST\n";
     }
diff --git a/services/audiopolicy/service/SpatializerPoseController.h b/services/audiopolicy/service/SpatializerPoseController.h
index 546eba0..233f94c 100644
--- a/services/audiopolicy/service/SpatializerPoseController.h
+++ b/services/audiopolicy/service/SpatializerPoseController.h
@@ -116,18 +116,6 @@
     // convert fields to a printable string
     std::string toString(unsigned level) const;
 
-    static std::string toString(media::HeadTrackingMode mode) {
-        switch (mode) {
-            case media::HeadTrackingMode::STATIC:
-                return "STATIC";
-            case media::HeadTrackingMode::WORLD_RELATIVE:
-                return "WORLD_RELATIVE";
-            case media::HeadTrackingMode::SCREEN_RELATIVE:
-                return "SCREEN_RELATIVE";
-        }
-        return "EnumNotImplemented";
-    };
-
   private:
     mutable std::timed_mutex mMutex;
     Listener* const mListener;
diff --git a/services/camera/libcameraservice/CameraService.cpp b/services/camera/libcameraservice/CameraService.cpp
index 80410ab..09bb5a1 100644
--- a/services/camera/libcameraservice/CameraService.cpp
+++ b/services/camera/libcameraservice/CameraService.cpp
@@ -1698,7 +1698,13 @@
         return STATUS_ERROR(ERROR_ILLEGAL_ARGUMENT, msg.string());
     }
 
-    if (CameraServiceProxyWrapper::isCameraDisabled()) {
+    userid_t clientUserId = multiuser_get_user_id(clientUid);
+    int callingUid = CameraThreadState::getCallingUid();
+    if (clientUid == USE_CALLING_UID) {
+        clientUserId = multiuser_get_user_id(callingUid);
+    }
+
+    if (CameraServiceProxyWrapper::isCameraDisabled(clientUserId)) {
         String8 msg =
                 String8::format("Camera disabled by device policy");
         ALOGE("%s: %s", __FUNCTION__, msg.string());
@@ -1901,6 +1907,9 @@
             }
         }
 
+        // Enable/disable camera service watchdog
+        client->setCameraServiceWatchdog(mCameraServiceWatchdogEnabled);
+
         // Set rotate-and-crop override behavior
         if (mOverrideRotateAndCropMode != ANDROID_SCALER_ROTATE_AND_CROP_AUTO) {
             client->setRotateAndCropOverride(mOverrideRotateAndCropMode);
@@ -4842,6 +4851,8 @@
         return handleSetCameraMute(args);
     } else if (args.size() >= 2 && args[0] == String16("watch")) {
         return handleWatchCommand(args, in, out);
+    } else if (args.size() >= 2 && args[0] == String16("set-watchdog")) {
+        return handleSetCameraServiceWatchdog(args);
     } else if (args.size() == 1 && args[0] == String16("help")) {
         printHelp(out);
         return OK;
@@ -4935,6 +4946,28 @@
     return OK;
 }
 
+status_t CameraService::handleSetCameraServiceWatchdog(const Vector<String16>& args) {
+    int enableWatchdog = atoi(String8(args[1]));
+
+    if (enableWatchdog < 0 || enableWatchdog > 1) return BAD_VALUE;
+
+    Mutex::Autolock lock(mServiceLock);
+
+    mCameraServiceWatchdogEnabled = enableWatchdog;
+
+    const auto clients = mActiveClientManager.getAll();
+    for (auto& current : clients) {
+        if (current != nullptr) {
+            const auto basicClient = current->getValue();
+            if (basicClient.get() != nullptr) {
+                basicClient->setCameraServiceWatchdog(enableWatchdog);
+            }
+        }
+    }
+
+    return OK;
+}
+
 status_t CameraService::handleGetRotateAndCrop(int out) {
     Mutex::Autolock lock(mServiceLock);
 
diff --git a/services/camera/libcameraservice/CameraService.h b/services/camera/libcameraservice/CameraService.h
index d96ea00..c645c28 100644
--- a/services/camera/libcameraservice/CameraService.h
+++ b/services/camera/libcameraservice/CameraService.h
@@ -339,6 +339,9 @@
         // Set/reset camera mute
         virtual status_t setCameraMute(bool enabled) = 0;
 
+        // Set Camera service watchdog
+        virtual status_t setCameraServiceWatchdog(bool enabled) = 0;
+
         // The injection camera session to replace the internal camera
         // session.
         virtual status_t injectCamera(const String8& injectedCamId,
@@ -1198,6 +1201,9 @@
     // Handle 'watch' command as passed through 'cmd'
     status_t handleWatchCommand(const Vector<String16> &args, int inFd, int outFd);
 
+    // Set the camera service watchdog
+    status_t handleSetCameraServiceWatchdog(const Vector<String16>& args);
+
     // Enable tag monitoring of the given tags in provided clients
     status_t startWatchingTags(const Vector<String16> &args, int outFd);
 
@@ -1284,6 +1290,9 @@
     // Current camera mute mode
     bool mOverrideCameraMuteMode = false;
 
+    // Camera Service watchdog flag
+    bool mCameraServiceWatchdogEnabled = true;
+
     /**
      * A listener class that implements the IBinder::DeathRecipient interface
      * for use to call back the error state injected by the external camera, and
diff --git a/services/camera/libcameraservice/CameraServiceWatchdog.cpp b/services/camera/libcameraservice/CameraServiceWatchdog.cpp
index a169667..e101dd3 100644
--- a/services/camera/libcameraservice/CameraServiceWatchdog.cpp
+++ b/services/camera/libcameraservice/CameraServiceWatchdog.cpp
@@ -66,6 +66,17 @@
     }
 }
 
+void CameraServiceWatchdog::setEnabled(bool enable)
+{
+    AutoMutex _l(mEnabledLock);
+
+    if (enable) {
+        mEnabled = true;
+    } else {
+        mEnabled = false;
+    }
+}
+
 void CameraServiceWatchdog::stop(uint32_t tid)
 {
     AutoMutex _l(mWatchdogLock);
diff --git a/services/camera/libcameraservice/CameraServiceWatchdog.h b/services/camera/libcameraservice/CameraServiceWatchdog.h
index 29ddab1..e35d69e 100644
--- a/services/camera/libcameraservice/CameraServiceWatchdog.h
+++ b/services/camera/libcameraservice/CameraServiceWatchdog.h
@@ -21,10 +21,12 @@
  * expected duration has exceeded.
  * Notes on multi-threaded behaviors:
  *    - The threadloop is blocked/paused when there are no calls being
- *   monitored.
+ *   monitored (when the TID cycle to counter map is empty).
  *   - The start and stop functions handle simultaneous call monitoring
  *   and single call monitoring differently. See function documentation for
  *   more details.
+ * To disable/enable:
+ *   - adb shell cmd media.camera set-cameraservice-watchdog [0/1]
  */
 #pragma once
 #include <chrono>
@@ -49,15 +51,19 @@
 
 public:
     explicit CameraServiceWatchdog() : mPause(true), mMaxCycles(kMaxCycles),
-            mCycleLengthMs(kCycleLengthMs) {};
+            mCycleLengthMs(kCycleLengthMs), mEnabled(true) {};
 
-    explicit CameraServiceWatchdog (size_t maxCycles, uint32_t cycleLengthMs) :
-            mPause(true), mMaxCycles(maxCycles), mCycleLengthMs(cycleLengthMs) {};
+    explicit CameraServiceWatchdog (size_t maxCycles, uint32_t cycleLengthMs, bool enabled) :
+            mPause(true), mMaxCycles(maxCycles), mCycleLengthMs(cycleLengthMs), mEnabled(enabled)
+                    {};
 
     virtual ~CameraServiceWatchdog() {};
 
     virtual void requestExit();
 
+    /** Enables/disables the watchdog */
+    void setEnabled(bool enable);
+
     /** Used to wrap monitored calls in start and stop functions using custom timer values */
     template<typename T>
     auto watchThread(T func, uint32_t tid, uint32_t cycles, uint32_t cycleLength) {
@@ -66,9 +72,20 @@
         if (cycles != mMaxCycles || cycleLength != mCycleLengthMs) {
             // Create another instance of the watchdog to prevent disruption
             // of timer for current monitored calls
+
+            // Lock for mEnabled
+            mEnabledLock.lock();
             sp<CameraServiceWatchdog> tempWatchdog =
-                    new CameraServiceWatchdog(cycles, cycleLength);
-            tempWatchdog->run("CameraServiceWatchdog");
+                    new CameraServiceWatchdog(cycles, cycleLength, mEnabled);
+            mEnabledLock.unlock();
+
+            status_t status = tempWatchdog->run("CameraServiceWatchdog");
+            if (status != OK) {
+                ALOGE("Unable to watch thread: %s (%d)", strerror(-status), status);
+                res = watchThread(func, tid);
+                return res;
+            }
+
             res = tempWatchdog->watchThread(func, tid);
             tempWatchdog->requestExit();
             tempWatchdog.clear();
@@ -84,10 +101,16 @@
     /** Used to wrap monitored calls in start and stop functions using class timer values */
     template<typename T>
     auto watchThread(T func, uint32_t tid) {
+        decltype(func()) res;
+        AutoMutex _l(mEnabledLock);
 
-        start(tid);
-        auto res = func();
-        stop(tid);
+        if (mEnabled) {
+            start(tid);
+            res = func();
+            stop(tid);
+        } else {
+            res = func();
+        }
 
         return res;
     }
@@ -108,11 +131,13 @@
 
     virtual bool    threadLoop();
 
-    Mutex           mWatchdogLock;        // Lock for condition variable
-    Condition       mWatchdogCondition;   // Condition variable for stop/start
-    bool            mPause;               // True if thread is currently paused
-    uint32_t        mMaxCycles;           // Max cycles
-    uint32_t        mCycleLengthMs;       // Length of time elapsed per cycle
+    Mutex           mWatchdogLock;      // Lock for condition variable
+    Mutex           mEnabledLock;       // Lock for enabled status
+    Condition       mWatchdogCondition; // Condition variable for stop/start
+    bool            mPause;             // True if tid map is empty
+    uint32_t        mMaxCycles;         // Max cycles
+    uint32_t        mCycleLengthMs;     // Length of time elapsed per cycle
+    bool            mEnabled;           // True if watchdog is enabled
 
     std::unordered_map<uint32_t, uint32_t> tidToCycleCounterMap; // Thread Id to cycle counter map
 };
diff --git a/services/camera/libcameraservice/api1/Camera2Client.cpp b/services/camera/libcameraservice/api1/Camera2Client.cpp
index 68dc7f8..20bf73d 100644
--- a/services/camera/libcameraservice/api1/Camera2Client.cpp
+++ b/services/camera/libcameraservice/api1/Camera2Client.cpp
@@ -2316,6 +2316,10 @@
     return INVALID_OPERATION;
 }
 
+status_t Camera2Client::setCameraServiceWatchdog(bool enabled) {
+    return mDevice->setCameraServiceWatchdog(enabled);
+}
+
 status_t Camera2Client::setRotateAndCropOverride(uint8_t rotateAndCrop) {
     if (rotateAndCrop > ANDROID_SCALER_ROTATE_AND_CROP_AUTO) return BAD_VALUE;
 
diff --git a/services/camera/libcameraservice/api1/Camera2Client.h b/services/camera/libcameraservice/api1/Camera2Client.h
index c8dfc46..8081efa 100644
--- a/services/camera/libcameraservice/api1/Camera2Client.h
+++ b/services/camera/libcameraservice/api1/Camera2Client.h
@@ -90,6 +90,8 @@
     virtual bool            supportsCameraMute();
     virtual status_t        setCameraMute(bool enabled);
 
+    virtual status_t        setCameraServiceWatchdog(bool enabled);
+
     /**
      * Interface used by CameraService
      */
diff --git a/services/camera/libcameraservice/api2/CameraDeviceClient.cpp b/services/camera/libcameraservice/api2/CameraDeviceClient.cpp
index 5e91501..15df981 100644
--- a/services/camera/libcameraservice/api2/CameraDeviceClient.cpp
+++ b/services/camera/libcameraservice/api2/CameraDeviceClient.cpp
@@ -1730,6 +1730,10 @@
     return binder::Status::ok();
 }
 
+status_t CameraDeviceClient::setCameraServiceWatchdog(bool enabled) {
+    return mDevice->setCameraServiceWatchdog(enabled);
+}
+
 status_t CameraDeviceClient::setRotateAndCropOverride(uint8_t rotateAndCrop) {
     if (rotateAndCrop > ANDROID_SCALER_ROTATE_AND_CROP_AUTO) return BAD_VALUE;
 
diff --git a/services/camera/libcameraservice/api2/CameraDeviceClient.h b/services/camera/libcameraservice/api2/CameraDeviceClient.h
index c5aad6b..45915ba 100644
--- a/services/camera/libcameraservice/api2/CameraDeviceClient.h
+++ b/services/camera/libcameraservice/api2/CameraDeviceClient.h
@@ -206,6 +206,8 @@
     virtual status_t      stopWatchingTags(int out);
     virtual status_t      dumpWatchedEventsToVector(std::vector<std::string> &out);
 
+    virtual status_t      setCameraServiceWatchdog(bool enabled);
+
     /**
      * Device listener interface
      */
diff --git a/services/camera/libcameraservice/api2/CameraOfflineSessionClient.cpp b/services/camera/libcameraservice/api2/CameraOfflineSessionClient.cpp
index 9303fd2..beb655b 100644
--- a/services/camera/libcameraservice/api2/CameraOfflineSessionClient.cpp
+++ b/services/camera/libcameraservice/api2/CameraOfflineSessionClient.cpp
@@ -66,6 +66,10 @@
     return OK;
 }
 
+status_t CameraOfflineSessionClient::setCameraServiceWatchdog(bool) {
+    return OK;
+}
+
 status_t CameraOfflineSessionClient::setRotateAndCropOverride(uint8_t /*rotateAndCrop*/) {
     // Since we're not submitting more capture requests, changes to rotateAndCrop override
     // make no difference.
diff --git a/services/camera/libcameraservice/api2/CameraOfflineSessionClient.h b/services/camera/libcameraservice/api2/CameraOfflineSessionClient.h
index f2c42d8..9ea1093 100644
--- a/services/camera/libcameraservice/api2/CameraOfflineSessionClient.h
+++ b/services/camera/libcameraservice/api2/CameraOfflineSessionClient.h
@@ -84,6 +84,8 @@
     bool supportsCameraMute() override;
     status_t setCameraMute(bool enabled) override;
 
+    status_t setCameraServiceWatchdog(bool enabled) override;
+
     // permissions management
     status_t startCameraOps() override;
     status_t finishCameraOps() override;
diff --git a/services/camera/libcameraservice/common/CameraDeviceBase.h b/services/camera/libcameraservice/common/CameraDeviceBase.h
index 7e2f93c..69514f3 100644
--- a/services/camera/libcameraservice/common/CameraDeviceBase.h
+++ b/services/camera/libcameraservice/common/CameraDeviceBase.h
@@ -449,6 +449,11 @@
     virtual status_t setCameraMute(bool enabled) = 0;
 
     /**
+     * Enable/disable camera service watchdog
+     */
+    virtual status_t setCameraServiceWatchdog(bool enabled) = 0;
+
+    /**
      * Get the status tracker of the camera device
      */
     virtual wp<camera3::StatusTracker> getStatusTracker() = 0;
diff --git a/services/camera/libcameraservice/device3/Camera3Device.cpp b/services/camera/libcameraservice/device3/Camera3Device.cpp
index 7c2f34f..8eb7fd0 100644
--- a/services/camera/libcameraservice/device3/Camera3Device.cpp
+++ b/services/camera/libcameraservice/device3/Camera3Device.cpp
@@ -113,10 +113,6 @@
 
 status_t Camera3Device::initializeCommonLocked() {
 
-    /** Start watchdog thread */
-    mCameraServiceWatchdog = new CameraServiceWatchdog();
-    mCameraServiceWatchdog->run("CameraServiceWatchdog");
-
     /** Start up status tracker thread */
     mStatusTracker = new StatusTracker(this);
     status_t res = mStatusTracker->run(String8::format("C3Dev-%s-Status", mId.string()).string());
@@ -230,6 +226,15 @@
     // Hidl/AidlCamera3DeviceInjectionMethods
     mInjectionMethods = createCamera3DeviceInjectionMethods(this);
 
+    /** Start watchdog thread */
+    mCameraServiceWatchdog = new CameraServiceWatchdog();
+    res = mCameraServiceWatchdog->run("CameraServiceWatchdog");
+    if (res != OK) {
+        SET_ERR_L("Unable to start camera service watchdog thread: %s (%d)",
+                strerror(-res), res);
+        return res;
+    }
+
     return OK;
 }
 
@@ -2674,7 +2679,7 @@
 status_t Camera3Device::registerInFlight(uint32_t frameNumber,
         int32_t numBuffers, CaptureResultExtras resultExtras, bool hasInput,
         bool hasAppCallback, nsecs_t minExpectedDuration, nsecs_t maxExpectedDuration,
-        const std::set<std::set<String8>>& physicalCameraIds,
+        bool isFixedFps, const std::set<std::set<String8>>& physicalCameraIds,
         bool isStillCapture, bool isZslCapture, bool rotateAndCropAuto,
         const std::set<std::string>& cameraIdsWithZoom,
         const SurfaceMap& outputSurfaces, nsecs_t requestTimeNs) {
@@ -2683,7 +2688,7 @@
 
     ssize_t res;
     res = mInFlightMap.add(frameNumber, InFlightRequest(numBuffers, resultExtras, hasInput,
-            hasAppCallback, minExpectedDuration, maxExpectedDuration, physicalCameraIds,
+            hasAppCallback, minExpectedDuration, maxExpectedDuration, isFixedFps, physicalCameraIds,
             isStillCapture, isZslCapture, rotateAndCropAuto, cameraIdsWithZoom, requestTimeNs,
             outputSurfaces));
     if (res < 0) return res;
@@ -3243,16 +3248,18 @@
     return true;
 }
 
-std::pair<nsecs_t, nsecs_t> Camera3Device::RequestThread::calculateExpectedDurationRange(
-        const camera_metadata_t *request) {
-    std::pair<nsecs_t, nsecs_t> expectedRange(
+Camera3Device::RequestThread::ExpectedDurationInfo
+        Camera3Device::RequestThread::calculateExpectedDurationRange(
+                const camera_metadata_t *request) {
+    ExpectedDurationInfo expectedDurationInfo = {
             InFlightRequest::kDefaultMinExpectedDuration,
-            InFlightRequest::kDefaultMaxExpectedDuration);
+            InFlightRequest::kDefaultMaxExpectedDuration,
+            /*isFixedFps*/false};
     camera_metadata_ro_entry_t e = camera_metadata_ro_entry_t();
     find_camera_metadata_ro_entry(request,
             ANDROID_CONTROL_AE_MODE,
             &e);
-    if (e.count == 0) return expectedRange;
+    if (e.count == 0) return expectedDurationInfo;
 
     switch (e.data.u8[0]) {
         case ANDROID_CONTROL_AE_MODE_OFF:
@@ -3260,29 +3267,32 @@
                     ANDROID_SENSOR_EXPOSURE_TIME,
                     &e);
             if (e.count > 0) {
-                expectedRange.first = e.data.i64[0];
-                expectedRange.second = expectedRange.first;
+                expectedDurationInfo.minDuration = e.data.i64[0];
+                expectedDurationInfo.maxDuration = expectedDurationInfo.minDuration;
             }
             find_camera_metadata_ro_entry(request,
                     ANDROID_SENSOR_FRAME_DURATION,
                     &e);
             if (e.count > 0) {
-                expectedRange.first = std::max(e.data.i64[0], expectedRange.first);
-                expectedRange.second = expectedRange.first;
+                expectedDurationInfo.minDuration =
+                        std::max(e.data.i64[0], expectedDurationInfo.minDuration);
+                expectedDurationInfo.maxDuration = expectedDurationInfo.minDuration;
             }
+            expectedDurationInfo.isFixedFps = false;
             break;
         default:
             find_camera_metadata_ro_entry(request,
                     ANDROID_CONTROL_AE_TARGET_FPS_RANGE,
                     &e);
             if (e.count > 1) {
-                expectedRange.first = 1e9 / e.data.i32[1];
-                expectedRange.second = 1e9 / e.data.i32[0];
+                expectedDurationInfo.minDuration = 1e9 / e.data.i32[1];
+                expectedDurationInfo.maxDuration = 1e9 / e.data.i32[0];
             }
+            expectedDurationInfo.isFixedFps = (e.data.i32[1] == e.data.i32[0]);
             break;
     }
 
-    return expectedRange;
+    return expectedDurationInfo;
 }
 
 bool Camera3Device::RequestThread::skipHFRTargetFPSUpdate(int32_t tag,
@@ -3897,13 +3907,14 @@
                 isZslCapture = true;
             }
         }
-        auto expectedDurationRange = calculateExpectedDurationRange(settings);
+        auto expectedDurationInfo = calculateExpectedDurationRange(settings);
         res = parent->registerInFlight(halRequest->frame_number,
                 totalNumBuffers, captureRequest->mResultExtras,
                 /*hasInput*/halRequest->input_buffer != NULL,
                 hasCallback,
-                /*min*/expectedDurationRange.first,
-                /*max*/expectedDurationRange.second,
+                expectedDurationInfo.minDuration,
+                expectedDurationInfo.maxDuration,
+                expectedDurationInfo.isFixedFps,
                 requestedPhysicalCameras, isStillCapture, isZslCapture,
                 captureRequest->mRotateAndCropAuto, mPrevCameraIdsWithZoom,
                 (mUseHalBufManager) ? uniqueSurfaceIdMap :
@@ -4094,6 +4105,17 @@
     }
 }
 
+status_t Camera3Device::setCameraServiceWatchdog(bool enabled) {
+    Mutex::Autolock il(mInterfaceLock);
+    Mutex::Autolock l(mLock);
+
+    if (mCameraServiceWatchdog != NULL) {
+        mCameraServiceWatchdog->setEnabled(enabled);
+    }
+
+    return OK;
+}
+
 void Camera3Device::RequestThread::cleanUpFailedRequests(bool sendRequestError) {
     if (mNextRequests.empty()) {
         return;
diff --git a/services/camera/libcameraservice/device3/Camera3Device.h b/services/camera/libcameraservice/device3/Camera3Device.h
index f927b4d..bcb7695 100644
--- a/services/camera/libcameraservice/device3/Camera3Device.h
+++ b/services/camera/libcameraservice/device3/Camera3Device.h
@@ -281,6 +281,11 @@
      */
     status_t setCameraMute(bool enabled);
 
+    /**
+     * Enables/disables camera service watchdog
+     */
+    status_t setCameraServiceWatchdog(bool enabled);
+
     // Get the status trackeer for the camera device
     wp<camera3::StatusTracker> getStatusTracker() { return mStatusTracker; }
 
@@ -962,8 +967,13 @@
         // send request in mNextRequests to HAL in a batch. Return true = sucssess
         bool sendRequestsBatch();
 
-        // Calculate the expected (minimum, maximum) duration range for a request
-        std::pair<nsecs_t, nsecs_t> calculateExpectedDurationRange(
+        // Calculate the expected (minimum, maximum, isFixedFps) duration info for a request
+        struct ExpectedDurationInfo {
+            nsecs_t minDuration;
+            nsecs_t maxDuration;
+            bool isFixedFps;
+        };
+        ExpectedDurationInfo calculateExpectedDurationRange(
                 const camera_metadata_t *request);
 
         // Check and update latest session parameters based on the current request settings.
@@ -1082,7 +1092,7 @@
     status_t registerInFlight(uint32_t frameNumber,
             int32_t numBuffers, CaptureResultExtras resultExtras, bool hasInput,
             bool callback, nsecs_t minExpectedDuration, nsecs_t maxExpectedDuration,
-            const std::set<std::set<String8>>& physicalCameraIds,
+            bool isFixedFps, const std::set<std::set<String8>>& physicalCameraIds,
             bool isStillCapture, bool isZslCapture, bool rotateAndCropAuto,
             const std::set<std::string>& cameraIdsWithZoom, const SurfaceMap& outputSurfaces,
             nsecs_t requestTimeNs);
@@ -1334,6 +1344,9 @@
 
     // The current minimum expected frame duration based on AE_TARGET_FPS_RANGE
     nsecs_t mMinExpectedDuration = 0;
+    // Whether the camera device runs at fixed frame rate based on AE_MODE and
+    // AE_TARGET_FPS_RANGE
+    bool mIsFixedFps = false;
 
     // Injection camera related methods.
     class Camera3DeviceInjectionMethods : public virtual RefBase {
diff --git a/services/camera/libcameraservice/device3/Camera3FakeStream.h b/services/camera/libcameraservice/device3/Camera3FakeStream.h
index 8cecabd..a93d1da 100644
--- a/services/camera/libcameraservice/device3/Camera3FakeStream.h
+++ b/services/camera/libcameraservice/device3/Camera3FakeStream.h
@@ -100,7 +100,7 @@
 
     virtual status_t setBatchSize(size_t batchSize) override;
 
-    virtual void onMinDurationChanged(nsecs_t /*duration*/) {}
+    virtual void onMinDurationChanged(nsecs_t /*duration*/, bool /*fixedFps*/) {}
   protected:
 
     /**
diff --git a/services/camera/libcameraservice/device3/Camera3IOStreamBase.cpp b/services/camera/libcameraservice/device3/Camera3IOStreamBase.cpp
index add1483..f594f84 100644
--- a/services/camera/libcameraservice/device3/Camera3IOStreamBase.cpp
+++ b/services/camera/libcameraservice/device3/Camera3IOStreamBase.cpp
@@ -41,8 +41,10 @@
                 physicalCameraId, sensorPixelModesUsed, setId, isMultiResolution,
                 dynamicRangeProfile, streamUseCase, deviceTimeBaseIsRealtime, timestampBase),
         mTotalBufferCount(0),
+        mMaxCachedBufferCount(0),
         mHandoutTotalBufferCount(0),
         mHandoutOutputBufferCount(0),
+        mCachedOutputBufferCount(0),
         mFrameCount(0),
         mLastTimestamp(0) {
 
@@ -95,8 +97,8 @@
     lines.appendFormat("      Timestamp base: %d\n", getTimestampBase());
     lines.appendFormat("      Frames produced: %d, last timestamp: %" PRId64 " ns\n",
             mFrameCount, mLastTimestamp);
-    lines.appendFormat("      Total buffers: %zu, currently dequeued: %zu\n",
-            mTotalBufferCount, mHandoutTotalBufferCount);
+    lines.appendFormat("      Total buffers: %zu, currently dequeued: %zu, currently cached: %zu\n",
+            mTotalBufferCount, mHandoutTotalBufferCount, mCachedOutputBufferCount);
     write(fd, lines.string(), lines.size());
 
     Camera3Stream::dump(fd, args);
@@ -135,6 +137,14 @@
     return (mHandoutTotalBufferCount - mHandoutOutputBufferCount);
 }
 
+size_t Camera3IOStreamBase::getCachedOutputBufferCountLocked() const {
+    return mCachedOutputBufferCount;
+}
+
+size_t Camera3IOStreamBase::getMaxCachedOutputBuffersLocked() const {
+    return mMaxCachedBufferCount;
+}
+
 status_t Camera3IOStreamBase::disconnectLocked() {
     switch (mState) {
         case STATE_IN_RECONFIG:
diff --git a/services/camera/libcameraservice/device3/Camera3IOStreamBase.h b/services/camera/libcameraservice/device3/Camera3IOStreamBase.h
index f389d53..ca1f238 100644
--- a/services/camera/libcameraservice/device3/Camera3IOStreamBase.h
+++ b/services/camera/libcameraservice/device3/Camera3IOStreamBase.h
@@ -56,11 +56,18 @@
     int              getMaxTotalBuffers() const { return mTotalBufferCount; }
   protected:
     size_t            mTotalBufferCount;
+    // The maximum number of cached buffers allowed for this stream
+    size_t            mMaxCachedBufferCount;
+
     // sum of input and output buffers that are currently acquired by HAL
     size_t            mHandoutTotalBufferCount;
     // number of output buffers that are currently acquired by HAL. This will be
     // Redundant when camera3 streams are no longer bidirectional streams.
     size_t            mHandoutOutputBufferCount;
+    // number of cached output buffers that are currently queued in the camera
+    // server but not yet queued to the buffer queue.
+    size_t            mCachedOutputBufferCount;
+
     uint32_t          mFrameCount;
     // Last received output buffer's timestamp
     nsecs_t           mLastTimestamp;
@@ -97,6 +104,9 @@
 
     virtual size_t   getHandoutInputBufferCountLocked();
 
+    virtual size_t   getCachedOutputBufferCountLocked() const;
+    virtual size_t   getMaxCachedOutputBuffersLocked() const;
+
     virtual status_t getEndpointUsage(uint64_t *usage) const = 0;
 
     status_t getBufferPreconditionCheckLocked() const;
diff --git a/services/camera/libcameraservice/device3/Camera3OfflineSession.h b/services/camera/libcameraservice/device3/Camera3OfflineSession.h
index a799719..5ee6ca5 100644
--- a/services/camera/libcameraservice/device3/Camera3OfflineSession.h
+++ b/services/camera/libcameraservice/device3/Camera3OfflineSession.h
@@ -248,6 +248,9 @@
 
     // The current minimum expected frame duration based on AE_TARGET_FPS_RANGE
     nsecs_t mMinExpectedDuration = 0;
+    // Whether the camera device runs at fixed frame rate based on AE_MODE and
+    // AE_TARGET_FPS_RANGE
+    bool mIsFixedFps = false;
 
     // SetErrorInterface
     void setErrorState(const char *fmt, ...) override;
diff --git a/services/camera/libcameraservice/device3/Camera3OutputStream.cpp b/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
index 69163a5..8b3cf44 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
+++ b/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
@@ -419,6 +419,7 @@
     mLock.unlock();
 
     ANativeWindowBuffer *anwBuffer = container_of(buffer.buffer, ANativeWindowBuffer, handle);
+    bool bufferDeferred = false;
     /**
      * Return buffer back to ANativeWindow
      */
@@ -478,6 +479,7 @@
                         __FUNCTION__, mId, strerror(-res), res);
                 return res;
             }
+            bufferDeferred = true;
         } else {
             nsecs_t presentTime = mSyncToDisplay ?
                     syncTimestampToDisplayLocked(captureTime) : captureTime;
@@ -501,6 +503,10 @@
     }
     mLock.lock();
 
+    if (bufferDeferred) {
+        mCachedOutputBufferCount++;
+    }
+
     // Once a valid buffer has been returned to the queue, can no longer
     // dequeue all buffers for preallocation.
     if (buffer.status != CAMERA_BUFFER_STATUS_ERROR) {
@@ -696,10 +702,15 @@
                 !isVideoStream());
         if (forceChoreographer || defaultToChoreographer) {
             mSyncToDisplay = true;
+            // For choreographer synced stream, extra buffers aren't kept by
+            // camera service. So no need to update mMaxCachedBufferCount.
             mTotalBufferCount += kDisplaySyncExtraBuffer;
         } else if (defaultToSpacer) {
             mPreviewFrameSpacer = new PreviewFrameSpacer(this, mConsumer);
-            mTotalBufferCount ++;
+            // For preview frame spacer, the extra buffer is kept by camera
+            // service. So update mMaxCachedBufferCount.
+            mMaxCachedBufferCount = 1;
+            mTotalBufferCount += mMaxCachedBufferCount;
             res = mPreviewFrameSpacer->run(String8::format("PreviewSpacer-%d", mId).string());
             if (res != OK) {
                 ALOGE("%s: Unable to start preview spacer", __FUNCTION__);
@@ -968,6 +979,14 @@
     return true;
 }
 
+void Camera3OutputStream::onCachedBufferQueued() {
+    Mutex::Autolock l(mLock);
+    mCachedOutputBufferCount--;
+    // Signal whoever is waiting for the buffer to be returned to the buffer
+    // queue.
+    mOutputBufferReturnedSignal.signal();
+}
+
 status_t Camera3OutputStream::disconnectLocked() {
     status_t res;
 
@@ -1367,9 +1386,10 @@
     return OK;
 }
 
-void Camera3OutputStream::onMinDurationChanged(nsecs_t duration) {
+void Camera3OutputStream::onMinDurationChanged(nsecs_t duration, bool fixedFps) {
     Mutex::Autolock l(mLock);
     mMinExpectedDuration = duration;
+    mFixedFps = fixedFps;
 }
 
 void Camera3OutputStream::returnPrefetchedBuffersLocked() {
@@ -1402,17 +1422,21 @@
 
     const VsyncEventData& vsyncEventData = parcelableVsyncEventData.vsync;
     nsecs_t currentTime = systemTime();
+    nsecs_t minPresentT = mLastPresentTime + vsyncEventData.frameInterval / 2;
 
-    // Reset capture to present time offset if:
-    // - More than 1 second between frames.
-    // - The frame duration deviates from multiples of vsync frame intervals.
+    // Find the best presentation time without worrying about previous frame's
+    // presentation time if capture interval is more than kSpacingResetIntervalNs.
+    //
+    // When frame interval is more than 50 ms apart (3 vsyncs for 60hz refresh rate),
+    // there is little risk in starting over and finding the earliest vsync to latch onto.
+    // - Update captureToPresentTime offset to be used for later frames.
+    // - Example use cases:
+    //   - when frame rate drops down to below 20 fps, or
+    //   - A new streaming session starts (stopPreview followed by
+    //   startPreview)
+    //
     nsecs_t captureInterval = t - mLastCaptureTime;
-    float captureToVsyncIntervalRatio = 1.0f * captureInterval / vsyncEventData.frameInterval;
-    float ratioDeviation = std::fabs(
-            captureToVsyncIntervalRatio - std::roundf(captureToVsyncIntervalRatio));
-    if (captureInterval > kSpacingResetIntervalNs ||
-            ratioDeviation >= kMaxIntervalRatioDeviation) {
-        nsecs_t minPresentT = mLastPresentTime + vsyncEventData.frameInterval / 2;
+    if (captureInterval > kSpacingResetIntervalNs) {
         for (size_t i = 0; i < VsyncEventData::kFrameTimelinesLength; i++) {
             const auto& timeline = vsyncEventData.frameTimelines[i];
             if (timeline.deadlineTimestamp >= currentTime &&
@@ -1434,21 +1458,54 @@
     nsecs_t idealPresentT = t + mCaptureToPresentOffset;
     nsecs_t expectedPresentT = mLastPresentTime;
     nsecs_t minDiff = INT64_MAX;
-    // Derive minimum intervals between presentation times based on minimal
+
+    // In fixed FPS case, when frame durations are close to multiples of display refresh
+    // rate, derive minimum intervals between presentation times based on minimal
     // expected duration. The minimum number of Vsyncs is:
     // - 0 if minFrameDuration in (0, 1.5] * vSyncInterval,
     // - 1 if minFrameDuration in (1.5, 2.5] * vSyncInterval,
     // - and so on.
+    //
+    // This spaces out the displaying of the frames so that the frame
+    // presentations are roughly in sync with frame captures.
     int minVsyncs = (mMinExpectedDuration - vsyncEventData.frameInterval / 2) /
             vsyncEventData.frameInterval;
     if (minVsyncs < 0) minVsyncs = 0;
     nsecs_t minInterval = minVsyncs * vsyncEventData.frameInterval;
+
+    // In fixed FPS case, if the frame duration deviates from multiples of
+    // display refresh rate, find the closest Vsync without requiring a minimum
+    // number of Vsync.
+    //
+    // Example: (24fps camera, 60hz refresh):
+    //   capture readout:  |  t1  |  t1  | .. |  t1  | .. |  t1  | .. |  t1  |
+    //   display VSYNC:      | t2 | t2 | ... | t2 | ... | t2 | ... | t2 |
+    //   |  : 1 frame
+    //   t1 : 41.67ms
+    //   t2 : 16.67ms
+    //   t1/t2 = 2.5
+    //
+    //   24fps is a commonly used video frame rate. Because the capture
+    //   interval is 2.5 times of display refresh interval, the minVsyncs
+    //   calculation will directly fall at the boundary condition. In this case,
+    //   we should fall back to the basic logic of finding closest vsync
+    //   timestamp without worrying about minVsyncs.
+    float captureToVsyncIntervalRatio = 1.0f * mMinExpectedDuration / vsyncEventData.frameInterval;
+    float ratioDeviation = std::fabs(
+            captureToVsyncIntervalRatio - std::roundf(captureToVsyncIntervalRatio));
+    bool captureDeviateFromVsync = ratioDeviation >= kMaxIntervalRatioDeviation;
+    bool cameraDisplayInSync = (mFixedFps && !captureDeviateFromVsync);
+
     // Find best timestamp in the vsync timelines:
-    // - Only use at most 3 timelines to avoid long latency
-    // - closest to the ideal present time,
+    // - Only use at most kMaxTimelines timelines to avoid long latency
+    // - closest to the ideal presentation time,
     // - deadline timestamp is greater than the current time, and
-    // - the candidate present time is at least minInterval in the future
-    //   compared to last present time.
+    // - For fixed FPS, if the capture interval doesn't deviate too much from refresh interval,
+    //   the candidate presentation time is at least minInterval in the future compared to last
+    //   presentation time.
+    // - For variable FPS, or if the capture interval deviates from refresh
+    //   interval for more than 5%, find a presentation time closest to the
+    //   (lastPresentationTime + captureToPresentOffset) instead.
     int maxTimelines = std::min(kMaxTimelines, (int)VsyncEventData::kFrameTimelinesLength);
     float biasForShortDelay = 1.0f;
     for (int i = 0; i < maxTimelines; i ++) {
@@ -1461,12 +1518,50 @@
         }
         if (std::abs(vsyncTime.expectedPresentationTime - idealPresentT) < minDiff &&
                 vsyncTime.deadlineTimestamp >= currentTime &&
-                vsyncTime.expectedPresentationTime >
-                mLastPresentTime + minInterval + biasForShortDelay * kTimelineThresholdNs) {
+                ((!cameraDisplayInSync && vsyncTime.expectedPresentationTime > minPresentT) ||
+                 (cameraDisplayInSync && vsyncTime.expectedPresentationTime >
+                mLastPresentTime + minInterval + biasForShortDelay * kTimelineThresholdNs))) {
             expectedPresentT = vsyncTime.expectedPresentationTime;
             minDiff = std::abs(vsyncTime.expectedPresentationTime - idealPresentT);
         }
     }
+
+    if (expectedPresentT == mLastPresentTime && expectedPresentT <=
+            vsyncEventData.frameTimelines[maxTimelines].expectedPresentationTime) {
+        // Couldn't find a reasonable presentation time. Using last frame's
+        // presentation time would cause a frame drop. The best option now
+        // is to use the next VSync as long as the last presentation time
+        // doesn't already has the maximum latency, in which case dropping the
+        // buffer is more desired than increasing latency.
+        //
+        // Example: (60fps camera, 59.9hz refresh):
+        //   capture readout:  | t1 | t1 | .. | t1 | .. | t1 | .. | t1 |
+        //                      \    \    \     \    \    \    \     \   \
+        //   queue to BQ:       |    |    |     |    |    |    |      |    |
+        //                      \    \    \     \    \     \    \      \    \
+        //   display VSYNC:      | t2 | t2 | ... | t2 | ... | t2 | ... | t2 |
+        //
+        //   |: 1 frame
+        //   t1 : 16.67ms
+        //   t2 : 16.69ms
+        //
+        // It takes 833 frames for capture readout count and display VSYNC count to be off
+        // by 1.
+        //  - At frames [0, 832], presentationTime is set to timeline[0]
+        //  - At frames [833, 833*2-1], presentationTime is set to timeline[1]
+        //  - At frames [833*2, 833*3-1] presentationTime is set to timeline[2]
+        //  - At frame 833*3, no presentation time is found because we only
+        //    search for timeline[0..2].
+        //  - Drop one buffer is better than further extend the presentation
+        //    time.
+        //
+        // However, if frame 833*2 arrives 16.67ms early (right after frame
+        // 833*2-1), no presentation time can be found because
+        // getLatestVsyncEventData is called early. In that case, it's better to
+        // set presentation time by offseting last presentation time.
+        expectedPresentT += vsyncEventData.frameInterval;
+    }
+
     mLastCaptureTime = t;
     mLastPresentTime = expectedPresentT;
 
diff --git a/services/camera/libcameraservice/device3/Camera3OutputStream.h b/services/camera/libcameraservice/device3/Camera3OutputStream.h
index 3587af4..741bca2 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputStream.h
+++ b/services/camera/libcameraservice/device3/Camera3OutputStream.h
@@ -247,9 +247,10 @@
     virtual status_t setBatchSize(size_t batchSize = 1) override;
 
     /**
-     * Notify the stream on change of min frame durations.
+     * Notify the stream on change of min frame durations or variable/fixed
+     * frame rate.
      */
-    virtual void onMinDurationChanged(nsecs_t duration) override;
+    virtual void onMinDurationChanged(nsecs_t duration, bool fixedFps) override;
 
     /**
      * Apply ZSL related consumer usage quirk.
@@ -258,6 +259,7 @@
 
     void setImageDumpMask(int mask) { mImageDumpMask = mask; }
     bool shouldLogError(status_t res);
+    void onCachedBufferQueued();
 
   protected:
     Camera3OutputStream(int id, camera_stream_type_t type,
@@ -419,6 +421,7 @@
 
     // Re-space frames by overriding timestamp to align with display Vsync.
     // Default is on for SurfaceView bound streams.
+    bool    mFixedFps = false;
     nsecs_t mMinExpectedDuration = 0;
     bool mSyncToDisplay = false;
     DisplayEventReceiver mDisplayEventReceiver;
diff --git a/services/camera/libcameraservice/device3/Camera3OutputStreamInterface.h b/services/camera/libcameraservice/device3/Camera3OutputStreamInterface.h
index a6d4b96..dbc6fe1 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputStreamInterface.h
+++ b/services/camera/libcameraservice/device3/Camera3OutputStreamInterface.h
@@ -110,12 +110,13 @@
     virtual status_t setBatchSize(size_t batchSize = 1) = 0;
 
     /**
-     * Notify the output stream that the minimum frame duration has changed.
+     * Notify the output stream that the minimum frame duration has changed, or
+     * frame rate has switched between variable and fixed.
      *
      * The minimum frame duration is calculated based on the upper bound of
      * AE_TARGET_FPS_RANGE in the capture request.
      */
-    virtual void onMinDurationChanged(nsecs_t duration) = 0;
+    virtual void onMinDurationChanged(nsecs_t duration, bool fixedFps) = 0;
 };
 
 // Helper class to organize a synchronized mapping of stream IDs to stream instances
diff --git a/services/camera/libcameraservice/device3/Camera3OutputUtils.cpp b/services/camera/libcameraservice/device3/Camera3OutputUtils.cpp
index f4e3fad..e16982b 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputUtils.cpp
+++ b/services/camera/libcameraservice/device3/Camera3OutputUtils.cpp
@@ -858,12 +858,14 @@
                 r.resultExtras.hasReadoutTimestamp = true;
                 r.resultExtras.readoutTimestamp = msg.readout_timestamp;
             }
-            if (r.minExpectedDuration != states.minFrameDuration) {
+            if (r.minExpectedDuration != states.minFrameDuration ||
+                    r.isFixedFps != states.isFixedFps) {
                 for (size_t i = 0; i < states.outputStreams.size(); i++) {
                     auto outputStream = states.outputStreams[i];
-                    outputStream->onMinDurationChanged(r.minExpectedDuration);
+                    outputStream->onMinDurationChanged(r.minExpectedDuration, r.isFixedFps);
                 }
                 states.minFrameDuration = r.minExpectedDuration;
+                states.isFixedFps = r.isFixedFps;
             }
             if (r.hasCallback) {
                 ALOGVV("Camera %s: %s: Shutter fired for frame %d (id %d) at %" PRId64,
diff --git a/services/camera/libcameraservice/device3/Camera3OutputUtils.h b/services/camera/libcameraservice/device3/Camera3OutputUtils.h
index d6107c2..8c71c2b 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputUtils.h
+++ b/services/camera/libcameraservice/device3/Camera3OutputUtils.h
@@ -106,6 +106,7 @@
         BufferRecordsInterface& bufferRecordsIntf;
         bool legacyClient;
         nsecs_t& minFrameDuration;
+        bool& isFixedFps;
     };
 
     void processCaptureResult(CaptureOutputStates& states, const camera_capture_result *result);
diff --git a/services/camera/libcameraservice/device3/Camera3Stream.cpp b/services/camera/libcameraservice/device3/Camera3Stream.cpp
index 7ad6649..88be9ff 100644
--- a/services/camera/libcameraservice/device3/Camera3Stream.cpp
+++ b/services/camera/libcameraservice/device3/Camera3Stream.cpp
@@ -665,11 +665,19 @@
         }
     }
 
-    // Wait for new buffer returned back if we are running into the limit.
+    // Wait for new buffer returned back if we are running into the limit. There
+    // are 2 limits:
+    // 1. The number of HAL buffers is greater than max_buffers
+    // 2. The number of HAL buffers + cached buffers is greater than max_buffers
+    //    + maxCachedBuffers
     size_t numOutstandingBuffers = getHandoutOutputBufferCountLocked();
-    if (numOutstandingBuffers == camera_stream::max_buffers) {
-        ALOGV("%s: Already dequeued max output buffers (%d), wait for next returned one.",
-                        __FUNCTION__, camera_stream::max_buffers);
+    size_t numCachedBuffers = getCachedOutputBufferCountLocked();
+    size_t maxNumCachedBuffers = getMaxCachedOutputBuffersLocked();
+    while (numOutstandingBuffers == camera_stream::max_buffers ||
+            numOutstandingBuffers + numCachedBuffers ==
+            camera_stream::max_buffers + maxNumCachedBuffers) {
+        ALOGV("%s: Already dequeued max output buffers (%d(+%zu)), wait for next returned one.",
+                        __FUNCTION__, camera_stream::max_buffers, maxNumCachedBuffers);
         nsecs_t waitStart = systemTime(SYSTEM_TIME_MONOTONIC);
         if (waitBufferTimeout < kWaitForBufferDuration) {
             waitBufferTimeout = kWaitForBufferDuration;
@@ -687,12 +695,16 @@
         }
 
         size_t updatedNumOutstandingBuffers = getHandoutOutputBufferCountLocked();
-        if (updatedNumOutstandingBuffers >= numOutstandingBuffers) {
-            ALOGE("%s: outsanding buffer count goes from %zu to %zu, "
+        size_t updatedNumCachedBuffers = getCachedOutputBufferCountLocked();
+        if (updatedNumOutstandingBuffers >= numOutstandingBuffers &&
+                updatedNumCachedBuffers == numCachedBuffers) {
+            ALOGE("%s: outstanding buffer count goes from %zu to %zu, "
                     "getBuffer(s) call must not run in parallel!", __FUNCTION__,
                     numOutstandingBuffers, updatedNumOutstandingBuffers);
             return INVALID_OPERATION;
         }
+        numOutstandingBuffers = updatedNumOutstandingBuffers;
+        numCachedBuffers = updatedNumCachedBuffers;
     }
 
     res = getBufferLocked(buffer, surface_ids);
@@ -1057,11 +1069,20 @@
     }
 
     size_t numOutstandingBuffers = getHandoutOutputBufferCountLocked();
-    // Wait for new buffer returned back if we are running into the limit.
-    while (numOutstandingBuffers + numBuffersRequested > camera_stream::max_buffers) {
-        ALOGV("%s: Already dequeued %zu output buffers and requesting %zu (max is %d), waiting.",
-                __FUNCTION__, numOutstandingBuffers, numBuffersRequested,
-                camera_stream::max_buffers);
+    size_t numCachedBuffers = getCachedOutputBufferCountLocked();
+    size_t maxNumCachedBuffers = getMaxCachedOutputBuffersLocked();
+    // Wait for new buffer returned back if we are running into the limit. There
+    // are 2 limits:
+    // 1. The number of HAL buffers is greater than max_buffers
+    // 2. The number of HAL buffers + cached buffers is greater than max_buffers
+    //    + maxCachedBuffers
+    while (numOutstandingBuffers + numBuffersRequested > camera_stream::max_buffers ||
+            numOutstandingBuffers + numCachedBuffers + numBuffersRequested >
+            camera_stream::max_buffers + maxNumCachedBuffers) {
+        ALOGV("%s: Already dequeued %zu(+%zu) output buffers and requesting %zu "
+                "(max is %d(+%zu)), waiting.", __FUNCTION__, numOutstandingBuffers,
+                numCachedBuffers, numBuffersRequested, camera_stream::max_buffers,
+                maxNumCachedBuffers);
         nsecs_t waitStart = systemTime(SYSTEM_TIME_MONOTONIC);
         if (waitBufferTimeout < kWaitForBufferDuration) {
             waitBufferTimeout = kWaitForBufferDuration;
@@ -1078,13 +1099,16 @@
             return res;
         }
         size_t updatedNumOutstandingBuffers = getHandoutOutputBufferCountLocked();
-        if (updatedNumOutstandingBuffers >= numOutstandingBuffers) {
-            ALOGE("%s: outsanding buffer count goes from %zu to %zu, "
+        size_t updatedNumCachedBuffers = getCachedOutputBufferCountLocked();
+        if (updatedNumOutstandingBuffers >= numOutstandingBuffers &&
+                updatedNumCachedBuffers == numCachedBuffers) {
+            ALOGE("%s: outstanding buffer count goes from %zu to %zu, "
                     "getBuffer(s) call must not run in parallel!", __FUNCTION__,
                     numOutstandingBuffers, updatedNumOutstandingBuffers);
             return INVALID_OPERATION;
         }
         numOutstandingBuffers = updatedNumOutstandingBuffers;
+        numCachedBuffers = updatedNumCachedBuffers;
     }
 
     res = getBuffersLocked(buffers);
diff --git a/services/camera/libcameraservice/device3/Camera3Stream.h b/services/camera/libcameraservice/device3/Camera3Stream.h
index d429e6c..214618a 100644
--- a/services/camera/libcameraservice/device3/Camera3Stream.h
+++ b/services/camera/libcameraservice/device3/Camera3Stream.h
@@ -558,6 +558,10 @@
     // Get handout input buffer count.
     virtual size_t   getHandoutInputBufferCountLocked() = 0;
 
+    // Get cached output buffer count.
+    virtual size_t   getCachedOutputBufferCountLocked() const = 0;
+    virtual size_t   getMaxCachedOutputBuffersLocked() const = 0;
+
     // Get the usage flags for the other endpoint, or return
     // INVALID_OPERATION if they cannot be obtained.
     virtual status_t getEndpointUsage(uint64_t *usage) const = 0;
@@ -576,6 +580,8 @@
 
     uint64_t mUsage;
 
+    Condition mOutputBufferReturnedSignal;
+
   private:
     // Previously configured stream properties (post HAL override)
     uint64_t mOldUsage;
@@ -583,7 +589,6 @@
     int mOldFormat;
     android_dataspace mOldDataSpace;
 
-    Condition mOutputBufferReturnedSignal;
     Condition mInputBufferReturnedSignal;
     static const nsecs_t kWaitForBufferDuration = 3000000000LL; // 3000 ms
 
diff --git a/services/camera/libcameraservice/device3/InFlightRequest.h b/services/camera/libcameraservice/device3/InFlightRequest.h
index fa00495..444445b 100644
--- a/services/camera/libcameraservice/device3/InFlightRequest.h
+++ b/services/camera/libcameraservice/device3/InFlightRequest.h
@@ -152,6 +152,9 @@
     // For auto-exposure modes, equal to 1/(lower end of target FPS range)
     nsecs_t maxExpectedDuration;
 
+    // Whether the FPS range is fixed, aka, minFps == maxFps
+    bool isFixedFps;
+
     // Whether the result metadata for this request is to be skipped. The
     // result metadata should be skipped in the case of
     // REQUEST/RESULT error.
@@ -205,6 +208,7 @@
             hasCallback(true),
             minExpectedDuration(kDefaultMinExpectedDuration),
             maxExpectedDuration(kDefaultMaxExpectedDuration),
+            isFixedFps(false),
             skipResultMetadata(false),
             errorBufStrategy(ERROR_BUF_CACHE),
             stillCapture(false),
@@ -215,7 +219,7 @@
     }
 
     InFlightRequest(int numBuffers, CaptureResultExtras extras, bool hasInput,
-            bool hasAppCallback, nsecs_t minDuration, nsecs_t maxDuration,
+            bool hasAppCallback, nsecs_t minDuration, nsecs_t maxDuration, bool fixedFps,
             const std::set<std::set<String8>>& physicalCameraIdSet, bool isStillCapture,
             bool isZslCapture, bool rotateAndCropAuto, const std::set<std::string>& idsWithZoom,
             nsecs_t requestNs, const SurfaceMap& outSurfaces = SurfaceMap{}) :
@@ -229,6 +233,7 @@
             hasCallback(hasAppCallback),
             minExpectedDuration(minDuration),
             maxExpectedDuration(maxDuration),
+            isFixedFps(fixedFps),
             skipResultMetadata(false),
             errorBufStrategy(ERROR_BUF_CACHE),
             physicalCameraIds(physicalCameraIdSet),
diff --git a/services/camera/libcameraservice/device3/PreviewFrameSpacer.cpp b/services/camera/libcameraservice/device3/PreviewFrameSpacer.cpp
index 0439501..67f42b4 100644
--- a/services/camera/libcameraservice/device3/PreviewFrameSpacer.cpp
+++ b/services/camera/libcameraservice/device3/PreviewFrameSpacer.cpp
@@ -122,6 +122,7 @@
         }
     }
 
+    parent->onCachedBufferQueued();
     mLastCameraPresentTime = currentTime;
     mLastCameraReadoutTime = bufferHolder.readoutTimestamp;
 }
diff --git a/services/camera/libcameraservice/device3/aidl/AidlCamera3Device.cpp b/services/camera/libcameraservice/device3/aidl/AidlCamera3Device.cpp
index f05520f..ec28d31 100644
--- a/services/camera/libcameraservice/device3/aidl/AidlCamera3Device.cpp
+++ b/services/camera/libcameraservice/device3/aidl/AidlCamera3Device.cpp
@@ -51,6 +51,7 @@
 
 #include <aidl/android/hardware/camera/device/ICameraInjectionSession.h>
 #include <aidlcommonsupport/NativeHandle.h>
+#include <android/binder_ibinder_platform.h>
 #include <android/hardware/camera2/ICameraDeviceUser.h>
 
 #include "utils/CameraTraces.h"
@@ -371,7 +372,8 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this,
-        *this, *(mInterface), mLegacyClient, mMinExpectedDuration}, mResultMetadataQueue
+        *this, *(mInterface), mLegacyClient, mMinExpectedDuration, mIsFixedFps},
+        mResultMetadataQueue
     };
 
     for (const auto& result : results) {
@@ -412,7 +414,8 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this,
-        *this, *(mInterface), mLegacyClient, mMinExpectedDuration}, mResultMetadataQueue
+        *this, *(mInterface), mLegacyClient, mMinExpectedDuration, mIsFixedFps},
+        mResultMetadataQueue
     };
     for (const auto& msg : msgs) {
         camera3::notify(states, msg);
@@ -669,6 +672,12 @@
     return p->returnStreamBuffers(buffers);
 }
 
+::ndk::SpAIBinder AidlCamera3Device::AidlCameraDeviceCallbacks::createBinder() {
+    auto binder = BnCameraDeviceCallback::createBinder();
+    AIBinder_setInheritRt(binder.get(), /*inheritRt*/ true);
+    return binder;
+}
+
 ::ndk::ScopedAStatus AidlCamera3Device::returnStreamBuffers(
         const std::vector<camera::device::StreamBuffer>& buffers) {
     ReturnBufferStates states {
diff --git a/services/camera/libcameraservice/device3/aidl/AidlCamera3Device.h b/services/camera/libcameraservice/device3/aidl/AidlCamera3Device.h
index d20a7eb..fd66661 100644
--- a/services/camera/libcameraservice/device3/aidl/AidlCamera3Device.h
+++ b/services/camera/libcameraservice/device3/aidl/AidlCamera3Device.h
@@ -242,6 +242,10 @@
         ::ndk::ScopedAStatus returnStreamBuffers(
                 const std::vector<
                         aidl::android::hardware::camera::device::StreamBuffer>& buffers) override;
+
+        protected:
+        ::ndk::SpAIBinder createBinder() override;
+
         private:
             wp<AidlCamera3Device> mParent = nullptr;
     };
diff --git a/services/camera/libcameraservice/device3/aidl/AidlCamera3OfflineSession.cpp b/services/camera/libcameraservice/device3/aidl/AidlCamera3OfflineSession.cpp
index 336719d..8ff0b07 100644
--- a/services/camera/libcameraservice/device3/aidl/AidlCamera3OfflineSession.cpp
+++ b/services/camera/libcameraservice/device3/aidl/AidlCamera3OfflineSession.cpp
@@ -30,6 +30,7 @@
 #include <utils/Trace.h>
 
 #include <android/hardware/camera2/ICameraDeviceCallbacks.h>
+#include <android/binder_ibinder_platform.h>
 
 #include "device3/aidl/AidlCamera3OfflineSession.h"
 #include "device3/Camera3OutputStream.h"
@@ -123,7 +124,8 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this,
-        *this, mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration}, mResultMetadataQueue
+        *this, mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration, mIsFixedFps},
+      mResultMetadataQueue
     };
 
     std::lock_guard<std::mutex> lock(mProcessCaptureResultLock);
@@ -168,7 +170,8 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this,
-        *this, mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration}, mResultMetadataQueue
+        *this, mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration, mIsFixedFps},
+      mResultMetadataQueue
     };
     for (const auto& msg : msgs) {
         camera3::notify(states, msg);
@@ -218,6 +221,12 @@
     return p->returnStreamBuffers(buffers);
 }
 
+::ndk::SpAIBinder AidlCamera3OfflineSession::AidlCameraDeviceCallbacks::createBinder() {
+    auto binder = BnCameraDeviceCallback::createBinder();
+    AIBinder_setInheritRt(binder.get(), /*inheritRt*/ true);
+    return binder;
+}
+
 ::ndk::ScopedAStatus AidlCamera3OfflineSession::returnStreamBuffers(
         const std::vector<camera::device::StreamBuffer>& buffers) {
     {
diff --git a/services/camera/libcameraservice/device3/aidl/AidlCamera3OfflineSession.h b/services/camera/libcameraservice/device3/aidl/AidlCamera3OfflineSession.h
index 33de2c5..d107af6 100644
--- a/services/camera/libcameraservice/device3/aidl/AidlCamera3OfflineSession.h
+++ b/services/camera/libcameraservice/device3/aidl/AidlCamera3OfflineSession.h
@@ -97,6 +97,10 @@
         ::ndk::ScopedAStatus returnStreamBuffers(
                 const std::vector<
                         aidl::android::hardware::camera::device::StreamBuffer>& buffers) override;
+        protected:
+
+        ::ndk::SpAIBinder createBinder() override;
+
         private:
             wp<AidlCamera3OfflineSession> mParent = nullptr;
     };
diff --git a/services/camera/libcameraservice/device3/hidl/HidlCamera3Device.cpp b/services/camera/libcameraservice/device3/hidl/HidlCamera3Device.cpp
index 4bb426c..9557692 100644
--- a/services/camera/libcameraservice/device3/hidl/HidlCamera3Device.cpp
+++ b/services/camera/libcameraservice/device3/hidl/HidlCamera3Device.cpp
@@ -363,7 +363,7 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this, *this,
-        *mInterface, mLegacyClient, mMinExpectedDuration}, mResultMetadataQueue
+        *mInterface, mLegacyClient, mMinExpectedDuration, mIsFixedFps}, mResultMetadataQueue
     };
 
     //HidlCaptureOutputStates hidlStates {
@@ -425,7 +425,7 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this, *this,
-        *mInterface, mLegacyClient, mMinExpectedDuration}, mResultMetadataQueue
+        *mInterface, mLegacyClient, mMinExpectedDuration, mIsFixedFps}, mResultMetadataQueue
     };
 
     for (const auto& result : results) {
@@ -472,7 +472,7 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this, *this,
-        *mInterface, mLegacyClient, mMinExpectedDuration}, mResultMetadataQueue
+        *mInterface, mLegacyClient, mMinExpectedDuration, mIsFixedFps}, mResultMetadataQueue
     };
     for (const auto& msg : msgs) {
         camera3::notify(states, msg);
diff --git a/services/camera/libcameraservice/device3/hidl/HidlCamera3OfflineSession.cpp b/services/camera/libcameraservice/device3/hidl/HidlCamera3OfflineSession.cpp
index 5c97f0e..2b4f8a1 100644
--- a/services/camera/libcameraservice/device3/hidl/HidlCamera3OfflineSession.cpp
+++ b/services/camera/libcameraservice/device3/hidl/HidlCamera3OfflineSession.cpp
@@ -105,7 +105,8 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this, *this,
-        mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration}, mResultMetadataQueue
+        mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration, mIsFixedFps},
+      mResultMetadataQueue
     };
 
     std::lock_guard<std::mutex> lock(mProcessCaptureResultLock);
@@ -145,7 +146,8 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this, *this,
-        mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration}, mResultMetadataQueue
+        mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration, mIsFixedFps},
+      mResultMetadataQueue
     };
 
     std::lock_guard<std::mutex> lock(mProcessCaptureResultLock);
@@ -180,7 +182,8 @@
         mNumPartialResults, mVendorTagId, mDeviceInfo, mPhysicalDeviceInfoMap,
         mDistortionMappers, mZoomRatioMappers, mRotateAndCropMappers,
         mTagMonitor, mInputStream, mOutputStreams, mSessionStatsBuilder, listener, *this, *this,
-        mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration}, mResultMetadataQueue
+        mBufferRecords, /*legacyClient*/ false, mMinExpectedDuration, mIsFixedFps},
+      mResultMetadataQueue
     };
     for (const auto& msg : msgs) {
         camera3::notify(states, msg);
diff --git a/services/camera/libcameraservice/utils/CameraServiceProxyWrapper.cpp b/services/camera/libcameraservice/utils/CameraServiceProxyWrapper.cpp
index 69175cc..dae5eea 100644
--- a/services/camera/libcameraservice/utils/CameraServiceProxyWrapper.cpp
+++ b/services/camera/libcameraservice/utils/CameraServiceProxyWrapper.cpp
@@ -262,11 +262,11 @@
     sessionStats->onClose(latencyMs);
 }
 
-bool CameraServiceProxyWrapper::isCameraDisabled() {
+bool CameraServiceProxyWrapper::isCameraDisabled(int userId) {
     sp<ICameraServiceProxy> proxyBinder = getCameraServiceProxy();
     if (proxyBinder == nullptr) return true;
     bool ret = false;
-    auto status = proxyBinder->isCameraDisabled(&ret);
+    auto status = proxyBinder->isCameraDisabled(userId, &ret);
     if (!status.isOk()) {
         ALOGE("%s: Failed during camera disabled query: %s", __FUNCTION__,
                 status.exceptionMessage().c_str());
diff --git a/services/camera/libcameraservice/utils/CameraServiceProxyWrapper.h b/services/camera/libcameraservice/utils/CameraServiceProxyWrapper.h
index e34a8f0..eb818d1 100644
--- a/services/camera/libcameraservice/utils/CameraServiceProxyWrapper.h
+++ b/services/camera/libcameraservice/utils/CameraServiceProxyWrapper.h
@@ -97,7 +97,7 @@
     static int getRotateAndCropOverride(String16 packageName, int lensFacing, int userId);
 
     // Detect if the camera is disabled by device policy.
-    static bool isCameraDisabled();
+    static bool isCameraDisabled(int userId);
 };
 
 } // android
diff --git a/services/mediametrics/AudioAnalytics.cpp b/services/mediametrics/AudioAnalytics.cpp
index 99e3691..b03e418 100644
--- a/services/mediametrics/AudioAnalytics.cpp
+++ b/services/mediametrics/AudioAnalytics.cpp
@@ -240,6 +240,35 @@
     "sharing_requested",
 };
 
+static constexpr const char * HeadTrackerDeviceEnabledFields[] {
+    "mediametrics_headtrackerdeviceenabled_reported",
+    "type",
+    "event",
+    "enabled",
+};
+
+static constexpr const char * HeadTrackerDeviceSupportedFields[] {
+    "mediametrics_headtrackerdevicesupported_reported",
+    "type",
+    "event",
+    "supported",
+};
+
+static constexpr const char * SpatializerCapabilitiesFields[] {
+    "mediametrics_spatializer_reported",
+    "head_tracking_modes",
+    "spatializer_levels",
+    "spatializer_modes",
+    "channel_masks",
+};
+
+static constexpr const char * SpatializerDeviceEnabledFields[] {
+    "mediametrics_spatializerdeviceenabled_reported",
+    "type",
+    "event",
+    "enabled",
+};
+
 /**
  * printFields is a helper method that prints the fields and corresponding values
  * in a human readable style.
@@ -459,6 +488,15 @@
             [this](const std::shared_ptr<const android::mediametrics::Item> &item){
                 mAudioPowerUsage.checkCreatePatch(item);
             }));
+
+    // Handle Spatializer - these keys are prefixed by "audio.spatializer."
+    mActions.addAction(
+        AMEDIAMETRICS_KEY_PREFIX_AUDIO_SPATIALIZER "*." AMEDIAMETRICS_PROP_EVENT,
+        std::monostate{}, /* match any event */
+        std::make_shared<AnalyticsActions::Function>(
+            [this](const std::shared_ptr<const android::mediametrics::Item> &item){
+                mSpatializer.onEvent(item);
+            }));
 }
 
 AudioAnalytics::~AudioAnalytics()
@@ -750,15 +788,9 @@
     int32_t frameCount = 0;
     mAudioAnalytics.mAnalyticsState->timeMachine().get(
             key, AMEDIAMETRICS_PROP_FRAMECOUNT, &frameCount);
-    std::string inputDevicePairs;
-    mAudioAnalytics.mAnalyticsState->timeMachine().get(
-            key, AMEDIAMETRICS_PROP_INPUTDEVICES, &inputDevicePairs);
     int32_t intervalCount = 0;
     mAudioAnalytics.mAnalyticsState->timeMachine().get(
             key, AMEDIAMETRICS_PROP_INTERVALCOUNT, &intervalCount);
-    std::string outputDevicePairs;
-    mAudioAnalytics.mAnalyticsState->timeMachine().get(
-            key, AMEDIAMETRICS_PROP_OUTPUTDEVICES, &outputDevicePairs);
     int32_t sampleRate = 0;
     mAudioAnalytics.mAnalyticsState->timeMachine().get(
             key, AMEDIAMETRICS_PROP_SAMPLERATE, &sampleRate);
@@ -766,53 +798,16 @@
     mAudioAnalytics.mAnalyticsState->timeMachine().get(
             key, AMEDIAMETRICS_PROP_FLAGS, &flags);
 
-    // We may have several devices.
-    // Accumulate the bit flags for input and output devices.
-    std::stringstream oss;
-    long_enum_type_t outputDeviceBits{};
-    {   // compute outputDevices
-        const auto devaddrvec = stringutils::getDeviceAddressPairs(outputDevicePairs);
-        for (const auto& [device, addr] : devaddrvec) {
-            if (oss.tellp() > 0) oss << "|";  // delimit devices with '|'.
-            oss << device;
-            outputDeviceBits += types::lookup<types::OUTPUT_DEVICE, long_enum_type_t>(device);
-        }
-    }
-    const std::string outputDevices = oss.str();
-
-    std::stringstream iss;
-    long_enum_type_t inputDeviceBits{};
-    {   // compute inputDevices
-        const auto devaddrvec = stringutils::getDeviceAddressPairs(inputDevicePairs);
-        for (const auto& [device, addr] : devaddrvec) {
-            if (iss.tellp() > 0) iss << "|";  // delimit devices with '|'.
-            iss << device;
-            inputDeviceBits += types::lookup<types::INPUT_DEVICE, long_enum_type_t>(device);
-        }
-    }
-    const std::string inputDevices = iss.str();
-
-    // Get connected device name if from bluetooth.
-    bool isBluetooth = false;
-
-    std::string inputDeviceNames;  // not filled currently.
-    std::string outputDeviceNames;
-    if (outputDevices.find("AUDIO_DEVICE_OUT_BLUETOOTH") != std::string::npos) {
-        isBluetooth = true;
-        outputDeviceNames = SUPPRESSED;
-#if 0   // TODO(b/161554630) sanitize name
-        mAudioAnalytics.mAnalyticsState->timeMachine().get(
-            "audio.device.bt_a2dp", AMEDIAMETRICS_PROP_NAME, &outputDeviceNames);
-        // Remove | if present
-        stringutils::replace(outputDeviceNames, "|", '?');
-        if (outputDeviceNames.size() > STATSD_DEVICE_NAME_MAX_LENGTH) {
-            outputDeviceNames.resize(STATSD_DEVICE_NAME_MAX_LENGTH); // truncate
-        }
-#endif
-    }
-
     switch (itemType) {
     case RECORD: {
+        std::string inputDevicePairs;
+        mAudioAnalytics.mAnalyticsState->timeMachine().get(
+                key, AMEDIAMETRICS_PROP_INPUTDEVICES, &inputDevicePairs);
+
+        const auto [ inputDeviceStatsd, inputDevices ] =
+                stringutils::parseInputDevicePairs(inputDevicePairs);
+        const std::string inputDeviceNames;  // not filled currently.
+
         std::string callerName;
         const bool clientCalled = mAudioAnalytics.mAnalyticsState->timeMachine().get(
                 key, AMEDIAMETRICS_PROP_CALLERNAME, &callerName) == OK;
@@ -848,7 +843,7 @@
 
         LOG(LOG_LEVEL) << "key:" << key
               << " id:" << id
-              << " inputDevices:" << inputDevices << "(" << inputDeviceBits
+              << " inputDevices:" << inputDevices << "(" << inputDeviceStatsd
               << ") inputDeviceNames:" << inputDeviceNames
               << " deviceTimeNs:" << deviceTimeNs
               << " encoding:" << encoding << "(" << encodingForStats
@@ -866,7 +861,7 @@
                 && mAudioAnalytics.mDeliverStatistics) {
             const auto [ result, str ] = sendToStatsd(AudioRecordDeviceUsageFields,
                     CONDITION(android::util::MEDIAMETRICS_AUDIORECORDDEVICEUSAGE_REPORTED)
-                    , ENUM_EXTRACT(inputDeviceBits)
+                    , ENUM_EXTRACT(inputDeviceStatsd)
                     , inputDeviceNames.c_str()
                     , deviceTimeNs
                     , ENUM_EXTRACT(encodingForStats)
@@ -895,18 +890,35 @@
                 key, AMEDIAMETRICS_PROP_UNDERRUN, &underrun);
 
         const bool isInput = types::isInputThreadType(type);
+
+        // get device information
+        std::string devicePairs;
+        std::string deviceStatsd;
+        std::string devices;
+        std::string deviceNames;
+        if (isInput) {
+            // Note we get the "last" device which is the one associated with group.
+            item->get(AMEDIAMETRICS_PROP_PREFIX_LAST AMEDIAMETRICS_PROP_INPUTDEVICES,
+                    &devicePairs);
+            std::tie(deviceStatsd, devices) = stringutils::parseInputDevicePairs(devicePairs);
+        } else {
+            // Note we get the "last" device which is the one associated with group.
+            item->get(AMEDIAMETRICS_PROP_PREFIX_LAST AMEDIAMETRICS_PROP_OUTPUTDEVICES,
+                    &devicePairs);
+            std::tie(deviceStatsd, devices) = stringutils::parseOutputDevicePairs(devicePairs);
+            deviceNames = mAudioAnalytics.getDeviceNamesFromOutputDevices(devices);
+        }
+
         const auto encodingForStats = types::lookup<types::ENCODING, short_enum_type_t>(encoding);
         const auto flagsForStats =
                 (isInput ? types::lookup<types::INPUT_FLAG, short_enum_type_t>(flags)
                         : types::lookup<types::OUTPUT_FLAG, short_enum_type_t>(flags));
         const auto typeForStats = types::lookup<types::THREAD_TYPE, short_enum_type_t>(type);
 
-        LOG(LOG_LEVEL) << "key:" << key
+         LOG(LOG_LEVEL) << "key:" << key
               << " id:" << id
-              << " inputDevices:" << inputDevices << "(" << inputDeviceBits
-              << ") outputDevices:" << outputDevices << "(" << outputDeviceBits
-              << ") inputDeviceNames:" << inputDeviceNames
-              << " outputDeviceNames:" << outputDeviceNames
+              << " devices:" << devices << "(" << deviceStatsd
+              << ") deviceNames:" << deviceNames
               << " deviceTimeNs:" << deviceTimeNs
               << " encoding:" << encoding << "(" << encodingForStats
               << ") frameCount:" << frameCount
@@ -919,8 +931,8 @@
         if (mAudioAnalytics.mDeliverStatistics) {
             const auto [ result, str ] = sendToStatsd(AudioThreadDeviceUsageFields,
                 CONDITION(android::util::MEDIAMETRICS_AUDIOTHREADDEVICEUSAGE_REPORTED)
-                , isInput ? ENUM_EXTRACT(inputDeviceBits) : ENUM_EXTRACT(outputDeviceBits)
-                , isInput ? inputDeviceNames.c_str() : outputDeviceNames.c_str()
+                , ENUM_EXTRACT(deviceStatsd)
+                , deviceNames.c_str()
                 , deviceTimeNs
                 , ENUM_EXTRACT(encodingForStats)
                 , frameCount
@@ -936,6 +948,15 @@
         }
     } break;
     case TRACK: {
+        std::string outputDevicePairs;
+        mAudioAnalytics.mAnalyticsState->timeMachine().get(
+                key, AMEDIAMETRICS_PROP_OUTPUTDEVICES, &outputDevicePairs);
+
+        const auto [ outputDeviceStatsd, outputDevices ] =
+                stringutils::parseOutputDevicePairs(outputDevicePairs);
+        const std::string outputDeviceNames =
+                mAudioAnalytics.getDeviceNamesFromOutputDevices(outputDevices);
+
         std::string callerName;
         const bool clientCalled = mAudioAnalytics.mAnalyticsState->timeMachine().get(
                 key, AMEDIAMETRICS_PROP_CALLERNAME, &callerName) == OK;
@@ -1003,7 +1024,7 @@
 
         LOG(LOG_LEVEL) << "key:" << key
               << " id:" << id
-              << " outputDevices:" << outputDevices << "(" << outputDeviceBits
+              << " outputDevices:" << outputDevices << "(" << outputDeviceStatsd
               << ") outputDeviceNames:" << outputDeviceNames
               << " deviceTimeNs:" << deviceTimeNs
               << " encoding:" << encoding << "(" << encodingForStats
@@ -1030,7 +1051,7 @@
                 && mAudioAnalytics.mDeliverStatistics) {
             const auto [ result, str ] = sendToStatsd(AudioTrackDeviceUsageFields,
                     CONDITION(android::util::MEDIAMETRICS_AUDIOTRACKDEVICEUSAGE_REPORTED)
-                    , ENUM_EXTRACT(outputDeviceBits)
+                    , ENUM_EXTRACT(outputDeviceStatsd)
                     , outputDeviceNames.c_str()
                     , deviceTimeNs
                     , ENUM_EXTRACT(encodingForStats)
@@ -1057,11 +1078,6 @@
         }
         } break;
     }
-
-    // Report this as needed.
-    if (isBluetooth) {
-        // report this for Bluetooth
-    }
 }
 
 // DeviceConnection helper class.
@@ -1525,5 +1541,191 @@
     return { s, n };
 }
 
+// Classifies the setting event for statsd (use generated statsd enums.proto constants).
+static int32_t classifySettingEvent(bool isSetAlready, bool withinBoot) {
+    if (isSetAlready) {
+        return util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__EVENT__SPATIALIZER_SETTING_EVENT_NORMAL;
+    }
+    if (withinBoot) {
+        return util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__EVENT__SPATIALIZER_SETTING_EVENT_BOOT;
+    }
+    return util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__EVENT__SPATIALIZER_SETTING_EVENT_FIRST;
+}
+
+void AudioAnalytics::Spatializer::onEvent(
+        const std::shared_ptr<const android::mediametrics::Item> &item)
+{
+    const auto key = item->getKey();
+
+    if (!startsWith(key, AMEDIAMETRICS_KEY_PREFIX_AUDIO_SPATIALIZER)) return;
+
+    const std::string suffix =
+            key.substr(std::size(AMEDIAMETRICS_KEY_PREFIX_AUDIO_SPATIALIZER) - 1);
+
+    std::string eventStr; // optional - find the actual event string.
+    (void)item->get(AMEDIAMETRICS_PROP_EVENT, &eventStr);
+
+    const size_t delim = suffix.find('.'); // note could use split.
+    if (delim == suffix.npos) {
+        // on create with suffix == "0" for the first spatializer effect.
+
+        std::string headTrackingModes;
+        (void)item->get(AMEDIAMETRICS_PROP_HEADTRACKINGMODES, &headTrackingModes);
+
+        std::string levels;
+        (void)item->get(AMEDIAMETRICS_PROP_LEVELS, &levels);
+
+        std::string modes;
+        (void)item->get(AMEDIAMETRICS_PROP_MODES, &modes);
+
+        std::string channelMasks;
+        (void)item->get(AMEDIAMETRICS_PROP_CHANNELMASKS, &channelMasks);
+
+        LOG(LOG_LEVEL) << "key:" << key
+                << " headTrackingModes:" << headTrackingModes
+                << " levels:" << levels
+                << " modes:" << modes
+                << " channelMasks:" << channelMasks
+                ;
+
+        const std::vector<int32_t> headTrackingModesVector =
+                types::vectorFromMap(headTrackingModes, types::getHeadTrackingModeMap());
+        const std::vector<int32_t> levelsVector =
+                types::vectorFromMap(levels, types::getSpatializerLevelMap());
+        const std::vector<int32_t> modesVector =
+                types::vectorFromMap(modes, types::getSpatializerModeMap());
+        const std::vector<int64_t> channelMasksVector =
+                types::channelMaskVectorFromString(channelMasks);
+
+        const auto [ result, str ] = sendToStatsd(SpatializerCapabilitiesFields,
+                CONDITION(android::util::MEDIAMETRICS_SPATIALIZERCAPABILITIES_REPORTED)
+                , headTrackingModesVector
+                , levelsVector
+                , modesVector
+                , channelMasksVector
+                );
+
+        mAudioAnalytics.mStatsdLog->log(
+                android::util::MEDIAMETRICS_SPATIALIZERCAPABILITIES_REPORTED, str);
+
+        std::lock_guard lg(mLock);
+        if (mFirstCreateTimeNs == 0) {
+            // Only update the create time once to prevent audioserver restart
+            // from looking like a boot.
+            mFirstCreateTimeNs = item->getTimestamp();
+        }
+        mSimpleLog.log("%s suffix: %s item: %s",
+                __func__, suffix.c_str(), item->toString().c_str());
+    } else {
+        std::string subtype = suffix.substr(0, delim);
+        if (subtype != "device") return; // not a device.
+
+        const std::string deviceType = suffix.substr(std::size("device.") - 1);
+
+        const int32_t deviceTypeStatsd =
+                types::lookup<types::AUDIO_DEVICE_INFO_TYPE, int32_t>(deviceType);
+
+        std::string address;
+        (void)item->get(AMEDIAMETRICS_PROP_ADDRESS, &address);
+        std::string enabled;
+        (void)item->get(AMEDIAMETRICS_PROP_ENABLED, &enabled);
+        std::string hasHeadTracker;
+        (void)item->get(AMEDIAMETRICS_PROP_HASHEADTRACKER, &hasHeadTracker);
+        std::string headTrackerEnabled;
+        (void)item->get(AMEDIAMETRICS_PROP_HEADTRACKERENABLED, &headTrackerEnabled);
+
+        std::lock_guard lg(mLock);
+
+        // Validate from our cached state
+
+        // Our deviceKey takes the device type and appends the address if any.
+        // This distinguishes different wireless devices for the purposes of tracking.
+        std::string deviceKey(deviceType);
+        deviceKey.append("_").append(address);
+        DeviceState& deviceState = mDeviceStateMap[deviceKey];
+
+        // check whether the settings event is within a certain time of spatializer creation.
+        const bool withinBoot =
+                item->getTimestamp() - mFirstCreateTimeNs < kBootDurationThreshold;
+
+        if (!enabled.empty()) {
+            if (enabled != deviceState.enabled) {
+                const int32_t settingEventStatsd =
+                        classifySettingEvent(!deviceState.enabled.empty(), withinBoot);
+                deviceState.enabled = enabled;
+                const bool enabledStatsd = enabled == "true";
+                const auto [ result, str ] = sendToStatsd(SpatializerDeviceEnabledFields,
+                        CONDITION(android::util::MEDIAMETRICS_SPATIALIZERDEVICEENABLED_REPORTED)
+                        , deviceTypeStatsd
+                        , settingEventStatsd
+                        , enabledStatsd
+                        );
+                mAudioAnalytics.mStatsdLog->log(
+                        android::util::MEDIAMETRICS_SPATIALIZERDEVICEENABLED_REPORTED, str);
+            }
+        }
+        if (!hasHeadTracker.empty()) {
+            if (hasHeadTracker != deviceState.hasHeadTracker) {
+                const int32_t settingEventStatsd =
+                        classifySettingEvent(!deviceState.hasHeadTracker.empty(), withinBoot);
+                deviceState.hasHeadTracker = hasHeadTracker;
+                const bool supportedStatsd = hasHeadTracker == "true";
+                const auto [ result, str ] = sendToStatsd(HeadTrackerDeviceSupportedFields,
+                        CONDITION(android::util::MEDIAMETRICS_HEADTRACKERDEVICESUPPORTED_REPORTED)
+                        , deviceTypeStatsd
+                        , settingEventStatsd
+                        , supportedStatsd
+                        );
+                mAudioAnalytics.mStatsdLog->log(
+                        android::util::MEDIAMETRICS_HEADTRACKERDEVICESUPPORTED_REPORTED, str);
+            }
+        }
+        if (!headTrackerEnabled.empty()) {
+            if (headTrackerEnabled != deviceState.headTrackerEnabled) {
+                const int32_t settingEventStatsd =
+                        classifySettingEvent(!deviceState.headTrackerEnabled.empty(), withinBoot);
+                deviceState.headTrackerEnabled = headTrackerEnabled;
+                const bool enabledStatsd = headTrackerEnabled == "true";
+                const auto [ result, str ] = sendToStatsd(HeadTrackerDeviceEnabledFields,
+                        CONDITION(android::util::MEDIAMETRICS_HEADTRACKERDEVICEENABLED_REPORTED)
+                        , deviceTypeStatsd
+                        , settingEventStatsd
+                        , enabledStatsd
+                        );
+                mAudioAnalytics.mStatsdLog->log(
+                        android::util::MEDIAMETRICS_HEADTRACKERDEVICEENABLED_REPORTED, str);
+            }
+        }
+        mSimpleLog.log("%s deviceKey: %s item: %s",
+                __func__, deviceKey.c_str(), item->toString().c_str());
+    }
+}
+
+std::pair<std::string, int32_t> AudioAnalytics::Spatializer::dump(
+        int32_t lines, const char *prefix) const
+{
+    std::lock_guard lg(mLock);
+    std::string s = mSimpleLog.dumpToString(prefix == nullptr ? "" : prefix, lines);
+    size_t n = std::count(s.begin(), s.end(), '\n');
+    return { s, n };
+}
+
+// This method currently suppresses the name.
+std::string AudioAnalytics::getDeviceNamesFromOutputDevices(std::string_view devices) const {
+    std::string deviceNames;
+    if (stringutils::hasBluetoothOutputDevice(devices)) {
+        deviceNames = SUPPRESSED;
+#if 0   // TODO(b/161554630) sanitize name
+        mAudioAnalytics.mAnalyticsState->timeMachine().get(
+            "audio.device.bt_a2dp", AMEDIAMETRICS_PROP_NAME, &deviceNames);
+        // Remove | if present
+        stringutils::replace(deviceNames, "|", '?');
+        if (deviceNames.size() > STATSD_DEVICE_NAME_MAX_LENGTH) {
+            deviceNames.resize(STATSD_DEVICE_NAME_MAX_LENGTH); // truncate
+        }
+#endif
+    }
+    return deviceNames;
+}
 
 } // namespace android::mediametrics
diff --git a/services/mediametrics/AudioTypes.cpp b/services/mediametrics/AudioTypes.cpp
index 6e24a58..d2b4aab 100644
--- a/services/mediametrics/AudioTypes.cpp
+++ b/services/mediametrics/AudioTypes.cpp
@@ -135,6 +135,94 @@
     return map;
 }
 
+// A map for the Java AudioDeviceInfo types to internal (native) output devices.
+const std::unordered_map<std::string, int32_t>& getAudioDeviceOutCompactMap() {
+    // DO NOT MODIFY VALUES (OK to add new ones).
+    static std::unordered_map<std::string, int32_t> map{
+        // should "unknown" go to AUDIO_DEVICE_NONE?
+        {"earpiece", AUDIO_DEVICE_OUT_EARPIECE},
+        {"speaker", AUDIO_DEVICE_OUT_SPEAKER},
+        {"headset", AUDIO_DEVICE_OUT_WIRED_HEADSET},
+        {"headphone", AUDIO_DEVICE_OUT_WIRED_HEADPHONE},
+        {"bt_sco", AUDIO_DEVICE_OUT_BLUETOOTH_SCO},
+        {"bt_sco_hs", AUDIO_DEVICE_OUT_BLUETOOTH_SCO_HEADSET},
+        {"bt_sco_carkit", AUDIO_DEVICE_OUT_BLUETOOTH_SCO_CARKIT},
+        {"bt_a2dp", AUDIO_DEVICE_OUT_BLUETOOTH_A2DP},
+        {"bt_a2dp_hp", AUDIO_DEVICE_OUT_BLUETOOTH_A2DP_HEADPHONES},
+        {"bt_a2dp_spk", AUDIO_DEVICE_OUT_BLUETOOTH_A2DP_SPEAKER},
+        {"aux_digital", AUDIO_DEVICE_OUT_AUX_DIGITAL},
+        {"hdmi", AUDIO_DEVICE_OUT_HDMI},
+        {"analog_dock", AUDIO_DEVICE_OUT_ANLG_DOCK_HEADSET},
+        {"digital_dock", AUDIO_DEVICE_OUT_DGTL_DOCK_HEADSET},
+        {"usb_accessory", AUDIO_DEVICE_OUT_USB_ACCESSORY},
+        {"usb_device", AUDIO_DEVICE_OUT_USB_DEVICE},
+        {"remote_submix", AUDIO_DEVICE_OUT_REMOTE_SUBMIX},
+        {"telephony_tx", AUDIO_DEVICE_OUT_TELEPHONY_TX},
+        {"line", AUDIO_DEVICE_OUT_LINE},
+        {"hdmi_arc", AUDIO_DEVICE_OUT_HDMI_ARC},
+        {"hdmi_earc", AUDIO_DEVICE_OUT_HDMI_EARC},
+        {"spdif", AUDIO_DEVICE_OUT_SPDIF},
+        {"fm_transmitter", AUDIO_DEVICE_OUT_FM},
+        {"aux_line", AUDIO_DEVICE_OUT_AUX_LINE},
+        {"speaker_safe", AUDIO_DEVICE_OUT_SPEAKER_SAFE},
+        {"ip", AUDIO_DEVICE_OUT_IP},
+        {"bus", AUDIO_DEVICE_OUT_BUS},
+        {"proxy", AUDIO_DEVICE_OUT_PROXY},
+        {"usb_headset", AUDIO_DEVICE_OUT_USB_HEADSET},
+        {"hearing_aid_out", AUDIO_DEVICE_OUT_HEARING_AID},
+        {"echo_canceller", AUDIO_DEVICE_OUT_ECHO_CANCELLER},
+        // default does not exist
+        {"ble_headset", AUDIO_DEVICE_OUT_BLE_HEADSET},
+        {"ble_speaker", AUDIO_DEVICE_OUT_BLE_SPEAKER},
+        {"ble_broadcast", AUDIO_DEVICE_OUT_BLE_BROADCAST},
+    };
+    return map;
+}
+
+// A map for the Java AudioDeviceInfo types.
+// This uses generated statsd enums.proto constants.
+const std::unordered_map<std::string, int32_t>& getAudioDeviceInfoTypeMap() {
+    // DO NOT MODIFY VALUES (OK to add new ones).
+    static std::unordered_map<std::string, int32_t> map{
+        {"unknown", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_UNKNOWN},
+        {"earpiece", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BUILTIN_EARPIECE},
+        {"speaker", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BUILTIN_SPEAKER},
+        {"headset", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_WIRED_HEADSET},
+        {"headphone", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_WIRED_HEADPHONES}, // sic
+        {"bt_sco", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLUETOOTH_SCO},
+        {"bt_sco_hs", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLUETOOTH_SCO},
+        {"bt_sco_carkit", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLUETOOTH_SCO},
+        {"bt_a2dp", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLUETOOTH_A2DP},
+        {"bt_a2dp_hp", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLUETOOTH_A2DP},
+        {"bt_a2dp_spk", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLUETOOTH_A2DP},
+        {"aux_digital", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_HDMI},
+        {"hdmi", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_HDMI},
+        {"analog_dock", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_DOCK},
+        {"digital_dock", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_DOCK},
+        {"usb_accessory", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_USB_ACCESSORY},
+        {"usb_device", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_USB_DEVICE},
+        {"usb_headset", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_USB_HEADSET},
+        {"remote_submix", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_REMOTE_SUBMIX},
+        {"telephony_tx", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_TELEPHONY},
+        {"line", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_LINE_ANALOG},
+        {"hdmi_arc", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_HDMI_ARC},
+        {"hdmi_earc", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_HDMI_EARC},
+        {"spdif", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_LINE_DIGITAL},
+        {"fm_transmitter", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_FM},
+        {"aux_line", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_AUX_LINE},
+        {"speaker_safe", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BUILTIN_SPEAKER_SAFE},
+        {"ip", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_IP},
+        {"bus", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BUS},
+        {"proxy", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_UNKNOWN /* AUDIO_DEVICE_INFO_TYPE_PROXY */},
+        {"hearing_aid_out", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_HEARING_AID},
+        {"echo_canceller", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_ECHO_REFERENCE}, // sic
+        {"ble_headset", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLE_HEADSET},
+        {"ble_speaker", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLE_SPEAKER},
+        {"ble_broadcast", util::MEDIAMETRICS_SPATIALIZER_DEVICE_ENABLED_REPORTED__TYPE__AUDIO_DEVICE_INFO_TYPE_BLE_BROADCAST},
+    };
+    return map;
+}
+
 const std::unordered_map<std::string, int32_t>& getAudioThreadTypeMap() {
     // DO NOT MODIFY VALUES (OK to add new ones).
     // This may be found in frameworks/av/services/audioflinger/Threads.h
@@ -197,6 +285,41 @@
     return map;
 }
 
+const std::unordered_map<std::string, int32_t>& getHeadTrackingModeMap() {
+    // DO NOT MODIFY VALUES(OK to add new ones).
+    // frameworks/base/media/java/android/media/Spatializer.java
+    // frameworks/av/media/libaudioclient/aidl/android/media/SpatializerHeadTrackingMode.aidl
+    static std::unordered_map<std::string, int32_t> map {
+        {"OTHER", 0},
+        {"DISABLED", -1},
+        {"RELATIVE_WORLD", 1},
+        {"RELATIVE_SCREEN", 2},
+    };
+    return map;
+}
+
+const std::unordered_map<std::string, int32_t>& getSpatializerLevelMap() {
+    // DO NOT MODIFY VALUES(OK to add new ones).
+    // frameworks/base/media/java/android/media/Spatializer.java
+    // frameworks/av/media/libaudioclient/aidl/android/media/SpatializerHeadTrackingMode.aidl
+    static std::unordered_map<std::string, int32_t> map {
+        {"NONE", 0},
+        {"SPATIALIZER_MULTICHANNEL", 1},
+        {"SPATIALIZER_MCHAN_BED_PLUS_OBJECTS", 2},
+    };
+    return map;
+}
+
+const std::unordered_map<std::string, int32_t>& getSpatializerModeMap() {
+    // DO NOT MODIFY VALUES(OK to add new ones).
+    // frameworks/av/media/libaudioclient/aidl/android/media/SpatializationMode.aidl
+    static std::unordered_map<std::string, int32_t> map {
+        {"SPATIALIZER_BINAURAL", 0},
+        {"SPATIALIZER_TRANSAURAL", 1},
+    };
+    return map;
+}
+
 const std::unordered_map<std::string, int32_t>& getStatusMap() {
     // DO NOT MODIFY VALUES(OK to add new ones).
     static std::unordered_map<std::string, int32_t> map {
@@ -286,6 +409,35 @@
     return value;
 }
 
+std::vector<int32_t> vectorFromMap(
+        const std::string &str, const std::unordered_map<std::string, int32_t>& map)
+{
+    std::vector<int32_t> v;
+
+    if (str.empty()) return v;
+
+    const auto result = stringutils::split(str, "|");
+    for (const auto &s : result) {
+        auto it = map.find(s);
+        if (it == map.end()) continue;
+        v.push_back(it->second);
+    }
+    return v;
+}
+
+std::vector<int64_t> channelMaskVectorFromString(const std::string &s)
+{
+    std::vector<int64_t> v;
+
+    const auto result = stringutils::split(s, "|");
+    for (const auto &mask : result) {
+        // 0 if undetected or if actually 0.
+        int64_t int64Mask = strtoll(mask.c_str(), nullptr, 0);
+        v.push_back(int64Mask);
+    }
+    return v;
+}
+
 template <>
 int32_t lookup<CONTENT_TYPE>(const std::string &contentType)
 {
@@ -441,6 +593,17 @@
 }
 
 template <>
+int32_t lookup<AUDIO_DEVICE_INFO_TYPE>(const std::string& audioDeviceInfoType)
+{
+    auto& map = getAudioDeviceInfoTypeMap();
+    auto it = map.find(audioDeviceInfoType);
+    if (it == map.end()) {
+        return 0;
+    }
+    return it->second;
+}
+
+template <>
 int32_t lookup<CALLER_NAME>(const std::string &callerName)
 {
     auto& map = getAudioCallerNameMap();
@@ -463,6 +626,39 @@
 }
 
 template <>
+int32_t lookup<HEAD_TRACKING_MODE>(const std::string& headTrackingMode)
+{
+    auto& map = getHeadTrackingModeMap();
+    auto it = map.find(headTrackingMode);
+    if (it == map.end()) {
+        return 0;
+    }
+    return it->second;
+}
+
+template <>
+int32_t lookup<SPATIALIZER_LEVEL>(const std::string& spatializerLevel)
+{
+    auto& map = getSpatializerLevelMap();
+    auto it = map.find(spatializerLevel);
+    if (it == map.end()) {
+        return 0;
+    }
+    return it->second;
+}
+
+template <>
+int32_t lookup<SPATIALIZER_MODE>(const std::string& spatializerMode)
+{
+    auto& map = getSpatializerModeMap();
+    auto it = map.find(spatializerMode);
+    if (it == map.end()) {
+        return 0;
+    }
+    return it->second;
+}
+
+template <>
 int32_t lookup<STATUS>(const std::string &status)
 {
     auto& map = getStatusMap();
diff --git a/services/mediametrics/MediaMetricsService.cpp b/services/mediametrics/MediaMetricsService.cpp
index ff16b9e..8a7e8a9 100644
--- a/services/mediametrics/MediaMetricsService.cpp
+++ b/services/mediametrics/MediaMetricsService.cpp
@@ -336,6 +336,15 @@
                 result << "-- some lines may be truncated --\n";
             }
 
+            const int32_t spatializerLinesToDump = all ? INT32_MAX : 15;
+            result << "\nSpatializer Message Log:";
+            const auto [ spatializerDumpString, spatializerLines ] =
+                    mAudioAnalytics.dumpSpatializer(spatializerLinesToDump);
+            result << "\n" << spatializerDumpString;
+            if (spatializerLines == spatializerLinesToDump) {
+                result << "-- some lines may be truncated --\n";
+            }
+
             result << "\nLogSessionId:\n"
                    << mediametrics::ValidateId::get()->dump();
 
diff --git a/services/mediametrics/StringUtils.cpp b/services/mediametrics/StringUtils.cpp
index 50525bc..d1c7a18 100644
--- a/services/mediametrics/StringUtils.cpp
+++ b/services/mediametrics/StringUtils.cpp
@@ -20,6 +20,8 @@
 
 #include "StringUtils.h"
 
+#include "AudioTypes.h"
+
 namespace android::mediametrics::stringutils {
 
 std::string tokenizer(std::string::const_iterator& it,
@@ -99,4 +101,30 @@
     return replaced;
 }
 
+template <types::AudioEnumCategory CATEGORY>
+std::pair<std::string /* external statsd */, std::string /* internal */>
+parseDevicePairs(const std::string& devicePairs) {
+    std::pair<std::string, std::string> result{};
+    const auto devaddrvec = stringutils::getDeviceAddressPairs(devicePairs);
+    for (const auto& [device, addr] : devaddrvec) { // addr ignored for now.
+        if (!result.second.empty()) {
+            result.second.append("|"); // delimit devices with '|'.
+            result.first.append("|");
+        }
+        result.second.append(device);
+        result.first.append(types::lookup<CATEGORY, std::string>(device));
+    }
+    return result;
+}
+
+std::pair<std::string /* external statsd */, std::string /* internal */>
+parseOutputDevicePairs(const std::string& devicePairs) {
+    return parseDevicePairs<types::OUTPUT_DEVICE>(devicePairs);
+}
+
+std::pair<std::string /* external statsd */, std::string /* internal */>
+parseInputDevicePairs(const std::string& devicePairs) {
+    return parseDevicePairs<types::INPUT_DEVICE>(devicePairs);
+}
+
 } // namespace android::mediametrics::stringutils
diff --git a/services/mediametrics/include/mediametricsservice/AudioAnalytics.h b/services/mediametrics/include/mediametricsservice/AudioAnalytics.h
index 5ee8c30..82e928e 100644
--- a/services/mediametrics/include/mediametricsservice/AudioAnalytics.h
+++ b/services/mediametrics/include/mediametricsservice/AudioAnalytics.h
@@ -92,6 +92,15 @@
         return mHealth.dump(lines);
     }
 
+    /**
+     * Returns a pair consisting of the dump string and the number of lines in the string.
+     *
+     * Spatializer dump.
+     */
+    std::pair<std::string, int32_t> dumpSpatializer(int32_t lines = INT32_MAX) const {
+        return mSpatializer.dump(lines);
+    }
+
     void clear() {
         // underlying state is locked.
         mPreviousAnalyticsState->clear();
@@ -152,6 +161,13 @@
      */
     std::string getThreadFromTrack(const std::string& track) const;
 
+    /**
+     * return the device name, if present.
+     *
+     * This is currently enabled only for Bluetooth output devices.
+     */
+    std::string getDeviceNamesFromOutputDevices(std::string_view devices) const;
+
     const bool mDeliverStatistics;
 
     // Actions is individually locked
@@ -317,6 +333,36 @@
         SimpleLog mSimpleLog GUARDED_BY(mLock) {64};
     } mHealth{*this};
 
+    // Spatializer is a nested class that tracks related messages.
+    class Spatializer {
+    public:
+        explicit Spatializer(AudioAnalytics &audioAnalytics)
+            : mAudioAnalytics(audioAnalytics) {}
+
+        // an item that starts with "audio.spatializer"
+        void onEvent(const std::shared_ptr<const android::mediametrics::Item> &item);
+
+        std::pair<std::string, int32_t> dump(
+                int32_t lines = INT32_MAX, const char *prefix = nullptr) const;
+
+    private:
+
+        // Current device state as strings:
+        // "" means unknown, "true" or "false".
+        struct DeviceState {
+            std::string enabled;
+            std::string hasHeadTracker;
+            std::string headTrackerEnabled;
+        };
+
+        AudioAnalytics& mAudioAnalytics;
+        static constexpr int64_t kBootDurationThreshold = 120 /* seconds */ * 1e9;
+        mutable std::mutex mLock;
+        int64_t mFirstCreateTimeNs GUARDED_BY(mLock) = 0;
+        std::map<std::string, DeviceState> mDeviceStateMap GUARDED_BY(mLock);
+        SimpleLog mSimpleLog GUARDED_BY(mLock) {64};
+    } mSpatializer{*this};
+
     AudioPowerUsage mAudioPowerUsage;
 };
 
diff --git a/services/mediametrics/include/mediametricsservice/AudioTypes.h b/services/mediametrics/include/mediametricsservice/AudioTypes.h
index 5dbff9b..b5fe28b 100644
--- a/services/mediametrics/include/mediametricsservice/AudioTypes.h
+++ b/services/mediametrics/include/mediametricsservice/AudioTypes.h
@@ -29,6 +29,14 @@
 const std::unordered_map<std::string, int64_t>& getAudioDeviceOutMap();
 const std::unordered_map<std::string, int32_t>& getAudioThreadTypeMap();
 const std::unordered_map<std::string, int32_t>& getAudioTrackTraitsMap();
+const std::unordered_map<std::string, int32_t>& getHeadTrackingModeMap();
+const std::unordered_map<std::string, int32_t>& getSpatializerLevelMap();
+const std::unordered_map<std::string, int32_t>& getSpatializerModeMap();
+
+std::vector<int32_t> vectorFromMap(
+        const std::string &str, const std::unordered_map<std::string, int32_t>& map);
+
+std::vector<int64_t> channelMaskVectorFromString(const std::string &s);
 
 // Enumeration for the device connection results.
 enum DeviceConnectionResult : int32_t {
@@ -47,14 +55,18 @@
     AAUDIO_DIRECTION,
     AAUDIO_PERFORMANCE_MODE,
     AAUDIO_SHARING_MODE,
+    AUDIO_DEVICE_INFO_TYPE,
     CALLER_NAME,
     CONTENT_TYPE,
     ENCODING,
+    HEAD_TRACKING_MODE,
     INPUT_DEVICE,  // int64_t
     INPUT_FLAG,
     OUTPUT_DEVICE, // int64_t
     OUTPUT_FLAG,
     SOURCE_TYPE,
+    SPATIALIZER_LEVEL,
+    SPATIALIZER_MODE,
     STATUS,
     STREAM_TYPE,
     THREAD_TYPE,
diff --git a/services/mediametrics/include/mediametricsservice/MediaMetricsService.h b/services/mediametrics/include/mediametricsservice/MediaMetricsService.h
index 8d0b1cf..3ec5ac7 100644
--- a/services/mediametrics/include/mediametricsservice/MediaMetricsService.h
+++ b/services/mediametrics/include/mediametricsservice/MediaMetricsService.h
@@ -125,7 +125,7 @@
     std::atomic<int64_t> mItemsSubmitted{}; // accessed outside of lock.
 
     // mStatsdLog is locked internally (thread-safe) and shows the last atoms logged
-    static constexpr size_t STATSD_LOG_LINES_MAX = 30; // recent log lines to keep
+    static constexpr size_t STATSD_LOG_LINES_MAX = 48; // recent log lines to keep
     static constexpr size_t STATSD_LOG_LINES_DUMP = 4; // normal amount of lines to dump
     const std::shared_ptr<mediametrics::StatsdLog> mStatsdLog{
             std::make_shared<mediametrics::StatsdLog>(STATSD_LOG_LINES_MAX)};
diff --git a/services/mediametrics/include/mediametricsservice/StringUtils.h b/services/mediametrics/include/mediametricsservice/StringUtils.h
index a56f5b8..78c25ff 100644
--- a/services/mediametrics/include/mediametricsservice/StringUtils.h
+++ b/services/mediametrics/include/mediametricsservice/StringUtils.h
@@ -23,6 +23,19 @@
 
 namespace android::mediametrics::stringutils {
 
+// Define a way of printing a vector - this
+// is used for proto repeated arguments.
+template <typename T>
+inline std::ostream & operator<< (std::ostream& s,
+                           std::vector<T> const& v) {
+    s << "{ ";
+    for (const auto& e : v) {
+        s << e << " ";
+    }
+    s << "}";
+    return s;
+}
+
 /**
  * fieldPrint is a helper method that logs to a stringstream a sequence of
  * field names (in a fixed size array) together with a variable number of arg parameters.
@@ -204,4 +217,14 @@
     return { key, "" };
 }
 
+std::pair<std::string /* external statsd */, std::string /* internal */>
+parseOutputDevicePairs(const std::string& outputDevicePairs);
+
+std::pair<std::string /* external statsd */, std::string /* internal */>
+parseInputDevicePairs(const std::string& inputDevicePairs);
+
+inline bool hasBluetoothOutputDevice(std::string_view devices) {
+    return devices.find("AUDIO_DEVICE_OUT_BLUETOOTH") != std::string::npos;
+}
+
 } // namespace android::mediametrics::stringutils
diff --git a/services/oboeservice/AAudioServiceEndpointMMAP.cpp b/services/oboeservice/AAudioServiceEndpointMMAP.cpp
index 3f18b95..ea817ab 100644
--- a/services/oboeservice/AAudioServiceEndpointMMAP.cpp
+++ b/services/oboeservice/AAudioServiceEndpointMMAP.cpp
@@ -71,6 +71,8 @@
 aaudio_result_t AAudioServiceEndpointMMAP::open(const aaudio::AAudioStreamRequest &request) {
     aaudio_result_t result = AAUDIO_OK;
     copyFrom(request.getConstantConfiguration());
+    mRequestedDeviceId = getDeviceId();
+
     mMmapClient.attributionSource = request.getAttributionSource();
     // TODO b/182392769: use attribution source util
     mMmapClient.attributionSource.uid = VALUE_OR_FATAL(
@@ -115,7 +117,7 @@
 
     const audio_attributes_t attributes = getAudioAttributesFrom(this);
 
-    mRequestedDeviceId = deviceId = getDeviceId();
+    deviceId = mRequestedDeviceId;
 
     // Fill in config
     config.format = audioFormat;
@@ -151,6 +153,10 @@
     audio_session_t sessionId = AAudioConvert_aaudioToAndroidSessionId(requestedSessionId);
 
     // Open HAL stream. Set mMmapStream
+    ALOGD("%s trying to open MMAP stream with format=%#x, "
+          "sample_rate=%u, channel_mask=%#x, device=%d",
+          __func__, config.format, config.sample_rate,
+          config.channel_mask, deviceId);
     status_t status = MmapStreamInterface::openMmapStream(streamDirection,
                                                           &attributes,
                                                           &config,
@@ -221,6 +227,9 @@
 
 error:
     close();
+    // restore original requests
+    setDeviceId(mRequestedDeviceId);
+    setSessionId(requestedSessionId);
     return result;
 }