diff --git a/camera/tests/Android.mk b/camera/tests/Android.mk
index e455943..ec13911 100644
--- a/camera/tests/Android.mk
+++ b/camera/tests/Android.mk
@@ -35,4 +35,4 @@
 LOCAL_MODULE:= camera_client_test
 LOCAL_MODULE_TAGS := tests
 
-include $(BUILD_EXECUTABLE)
+include $(BUILD_NATIVE_TEST)
diff --git a/cmds/stagefright/stagefright.cpp b/cmds/stagefright/stagefright.cpp
index 5bdbfbb..115b07c 100644
--- a/cmds/stagefright/stagefright.cpp
+++ b/cmds/stagefright/stagefright.cpp
@@ -523,7 +523,7 @@
     }
 
     sp<MetaData> params = new MetaData;
-    params->setInt32(kKeyNotRealTime, true);
+    params->setInt32(kKeyRealTimeRecording, false);
     CHECK_EQ(writer->start(params.get()), (status_t)OK);
 
     while (!writer->reachedEOS()) {
diff --git a/include/media/stagefright/MPEG4Writer.h b/include/media/stagefright/MPEG4Writer.h
index 88df6b0..3ef6b9a 100644
--- a/include/media/stagefright/MPEG4Writer.h
+++ b/include/media/stagefright/MPEG4Writer.h
@@ -74,6 +74,7 @@
 
     int  mFd;
     status_t mInitCheck;
+    bool mIsRealTimeRecording;
     bool mUse4ByteNalLength;
     bool mUse32BitOffset;
     bool mIsFileSizeLimitExplicitlyRequested;
@@ -168,6 +169,13 @@
     // Only makes sense for H.264/AVC
     bool useNalLengthFour();
 
+    // Return whether the writer is used for real time recording.
+    // In real time recording mode, new samples will be allowed to buffered into
+    // chunks in higher priority thread, even though the file writer has not
+    // drained the chunks yet.
+    // By default, real time recording is on.
+    bool isRealTimeRecording() const;
+
     void lock();
     void unlock();
 
diff --git a/include/media/stagefright/MetaData.h b/include/media/stagefright/MetaData.h
index 9ab3edc..de3fc36 100644
--- a/include/media/stagefright/MetaData.h
+++ b/include/media/stagefright/MetaData.h
@@ -112,7 +112,7 @@
     // kKeyTrackTimeStatus is used to track progress in elapsed time
     kKeyTrackTimeStatus   = 'tktm',  // int64_t
 
-    kKeyNotRealTime       = 'ntrt',  // bool (int32_t)
+    kKeyRealTimeRecording = 'rtrc',  // bool (int32_t)
     kKeyNumBuffers        = 'nbbf',  // int32_t
 
     // Ogg files can be tagged to be automatically looping...
diff --git a/libvideoeditor/vss/stagefrightshells/src/VideoEditorUtils.cpp b/libvideoeditor/vss/stagefrightshells/src/VideoEditorUtils.cpp
index 5309bd4..5a7237d 100755
--- a/libvideoeditor/vss/stagefrightshells/src/VideoEditorUtils.cpp
+++ b/libvideoeditor/vss/stagefrightshells/src/VideoEditorUtils.cpp
@@ -189,8 +189,8 @@
     if (meta->findInt64(kKeyTrackTimeStatus, &int64Data)) {
         LOG1("displayMetaData kKeyTrackTimeStatus %lld", int64Data);
     }
-    if (meta->findInt32(kKeyNotRealTime, &int32Data)) {
-        LOG1("displayMetaData kKeyNotRealTime %d", int32Data);
+    if (meta->findInt32(kKeyRealTimeRecording, &int32Data)) {
+        LOG1("displayMetaData kKeyRealTimeRecording %d", int32Data);
     }
 }
 
diff --git a/media/libmedia/mediaplayer.cpp b/media/libmedia/mediaplayer.cpp
index 3defec3..ecae3d3 100644
--- a/media/libmedia/mediaplayer.cpp
+++ b/media/libmedia/mediaplayer.cpp
@@ -398,6 +398,13 @@
     if (mPlayer != 0 && isValidState) {
         int durationMs;
         status_t ret = mPlayer->getDuration(&durationMs);
+
+        if (ret != OK) {
+            // Do not enter error state just because no duration was available.
+            durationMs = -1;
+            ret = OK;
+        }
+
         if (msec) {
             *msec = durationMs;
         }
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp b/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
index 723af09..bdafb29 100644
--- a/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
+++ b/media/libmediaplayerservice/nuplayer/NuPlayerDriver.cpp
@@ -314,11 +314,11 @@
     Mutex::Autolock autoLock(mLock);
 
     if (mDurationUs < 0) {
-        *msec = 0;
-    } else {
-        *msec = (mDurationUs + 500ll) / 1000;
+        return UNKNOWN_ERROR;
     }
 
+    *msec = (mDurationUs + 500ll) / 1000;
+
     return OK;
 }
 
diff --git a/media/libstagefright/MPEG4Writer.cpp b/media/libstagefright/MPEG4Writer.cpp
index 316f669..a0f17b5 100644
--- a/media/libstagefright/MPEG4Writer.cpp
+++ b/media/libstagefright/MPEG4Writer.cpp
@@ -212,7 +212,6 @@
     int64_t mTrackDurationUs;
     int64_t mMaxChunkDurationUs;
 
-    bool mIsRealTimeRecording;
     int64_t mEstimatedTrackSizeBytes;
     int64_t mMdatSizeBytes;
     int32_t mTimeScale;
@@ -335,6 +334,7 @@
 MPEG4Writer::MPEG4Writer(const char *filename)
     : mFd(-1),
       mInitCheck(NO_INIT),
+      mIsRealTimeRecording(true),
       mUse4ByteNalLength(true),
       mUse32BitOffset(true),
       mIsFileSizeLimitExplicitlyRequested(false),
@@ -359,6 +359,7 @@
 MPEG4Writer::MPEG4Writer(int fd)
     : mFd(dup(fd)),
       mInitCheck(mFd < 0? NO_INIT: OK),
+      mIsRealTimeRecording(true),
       mUse4ByteNalLength(true),
       mUse32BitOffset(true),
       mIsFileSizeLimitExplicitlyRequested(false),
@@ -596,6 +597,11 @@
         mUse4ByteNalLength = false;
     }
 
+    int32_t isRealTimeRecording;
+    if (param && param->findInt32(kKeyRealTimeRecording, &isRealTimeRecording)) {
+        mIsRealTimeRecording = isRealTimeRecording;
+    }
+
     mStartTimestampUs = -1;
 
     if (mStarted) {
@@ -1640,12 +1646,18 @@
             mChunkReadyCondition.wait(mLock);
         }
 
-        // Actual write without holding the lock in order to
-        // reduce the blocking time for media track threads.
+        // In real time recording mode, write without holding the lock in order
+        // to reduce the blocking time for media track threads.
+        // Otherwise, hold the lock until the existing chunks get written to the
+        // file.
         if (chunkFound) {
-            mLock.unlock();
+            if (mIsRealTimeRecording) {
+                mLock.unlock();
+            }
             writeChunkToFile(&chunk);
-            mLock.lock();
+            if (mIsRealTimeRecording) {
+                mLock.lock();
+            }
         }
     }
 
@@ -1695,18 +1707,10 @@
         mRotation = rotationDegrees;
     }
 
-    mIsRealTimeRecording = true;
-    {
-        int32_t isNotRealTime;
-        if (params && params->findInt32(kKeyNotRealTime, &isNotRealTime)) {
-            mIsRealTimeRecording = (isNotRealTime == 0);
-        }
-    }
-
     initTrackingProgressStatus(params);
 
     sp<MetaData> meta = new MetaData;
-    if (mIsRealTimeRecording && mOwner->numTracks() > 1) {
+    if (mOwner->isRealTimeRecording() && mOwner->numTracks() > 1) {
         /*
          * This extra delay of accepting incoming audio/video signals
          * helps to align a/v start time at the beginning of a recording
@@ -2084,7 +2088,10 @@
     } else {
         prctl(PR_SET_NAME, (unsigned long)"VideoTrackEncoding", 0, 0, 0);
     }
-    androidSetThreadPriority(0, ANDROID_PRIORITY_AUDIO);
+
+    if (mOwner->isRealTimeRecording()) {
+        androidSetThreadPriority(0, ANDROID_PRIORITY_AUDIO);
+    }
 
     sp<MetaData> meta_data;
 
@@ -2245,7 +2252,7 @@
 
         }
 
-        if (mIsRealTimeRecording) {
+        if (mOwner->isRealTimeRecording()) {
             if (mIsAudio) {
                 updateDriftTime(meta_data);
             }
@@ -2531,6 +2538,10 @@
     return mDriftTimeUs;
 }
 
+bool MPEG4Writer::isRealTimeRecording() const {
+    return mIsRealTimeRecording;
+}
+
 bool MPEG4Writer::useNalLengthFour() {
     return mUse4ByteNalLength;
 }
diff --git a/media/libstagefright/MediaMuxer.cpp b/media/libstagefright/MediaMuxer.cpp
index b948fe2..388c65b 100644
--- a/media/libstagefright/MediaMuxer.cpp
+++ b/media/libstagefright/MediaMuxer.cpp
@@ -107,6 +107,7 @@
     Mutex::Autolock autoLock(mMuxerLock);
     if (mState == INITIALIZED) {
         mState = STARTED;
+        mFileMeta->setInt32(kKeyRealTimeRecording, false);
         return mWriter->start(mFileMeta.get());
     } else {
         ALOGE("start() is called in invalid state %d", mState);
diff --git a/services/audioflinger/ISchedulingPolicyService.cpp b/services/audioflinger/ISchedulingPolicyService.cpp
index 909b77e..218aa6b 100644
--- a/services/audioflinger/ISchedulingPolicyService.cpp
+++ b/services/audioflinger/ISchedulingPolicyService.cpp
@@ -44,7 +44,7 @@
         data.writeInt32(pid);
         data.writeInt32(tid);
         data.writeInt32(prio);
-        remote()->transact(REQUEST_PRIORITY_TRANSACTION, data, &reply);
+        remote()->transact(REQUEST_PRIORITY_TRANSACTION, data, &reply, IBinder::FLAG_ONEWAY);
         // fail on exception
         if (reply.readExceptionCode() != 0) return -1;
         return reply.readInt32();