diff --git a/services/surfaceflinger/Scheduler/VSyncDispatch.h b/services/surfaceflinger/Scheduler/VSyncDispatch.h
index 0050495..4a4bef8 100644
--- a/services/surfaceflinger/Scheduler/VSyncDispatch.h
+++ b/services/surfaceflinger/Scheduler/VSyncDispatch.h
@@ -16,14 +16,9 @@
 
 #pragma once
 
-#include <android-base/thread_annotations.h>
 #include <utils/Timers.h>
 #include <functional>
-#include <memory>
-#include <mutex>
 #include <string>
-#include <string_view>
-#include <unordered_map>
 
 #include "StrongTyping.h"
 
@@ -34,68 +29,6 @@
 enum class ScheduleResult { Scheduled, ReScheduled, CannotSchedule, Error };
 enum class CancelResult { Cancelled, TooLate, Error };
 
-namespace impl {
-
-// VSyncDispatchEntry is a helper class representing internal state for each entry in VSyncDispatch
-// hoisted to public for unit testing.
-class VSyncDispatchEntry {
-public:
-    // This is the state of the entry. There are 3 states, armed, running, disarmed.
-    // Valid transition: disarmed -> armed ( when scheduled )
-    // Valid transition: armed -> running -> disarmed ( when timer is called)
-    // Valid transition: armed -> disarmed ( when cancelled )
-    VSyncDispatchEntry(std::string const& name, std::function<void(nsecs_t)> const& fn);
-    std::string_view name() const;
-
-    // Start: functions that are not threadsafe.
-    // Return the last vsync time this callback was invoked.
-    std::optional<nsecs_t> lastExecutedVsyncTarget() const;
-
-    // This moves the state from disarmed->armed and will calculate the wakeupTime.
-    nsecs_t schedule(nsecs_t workDuration, nsecs_t earliestVsync, VSyncTracker& tracker,
-                     nsecs_t now);
-    // This will update armed entries with the latest vsync information. Entry remains armed.
-    void update(VSyncTracker& tracker, nsecs_t now);
-
-    // This will return empty if not armed, or the next calculated wakeup time if armed.
-    // It will not update the wakeupTime.
-    std::optional<nsecs_t> wakeupTime() const;
-
-    // This moves state from armed->disarmed.
-    void disarm();
-
-    // This moves the state from armed->running.
-    // Store the timestamp that this was intended for as the last called timestamp.
-    nsecs_t executing();
-    // End: functions that are not threadsafe.
-
-    // Invoke the callback with the timestamp, moving the state from running->disarmed.
-    void callback(nsecs_t timestamp);
-    // Block calling thread while the callback is executing.
-    void ensureNotRunning();
-
-private:
-    void arm(VSyncTracker& tracker, nsecs_t now);
-    std::string const mName;
-    std::function<void(nsecs_t)> const mCallback;
-
-    nsecs_t mWorkDuration;
-    nsecs_t mEarliestVsync;
-
-    struct ArmingInfo {
-        nsecs_t mActualWakeupTime;
-        nsecs_t mActualVsyncTime;
-    };
-    std::optional<ArmingInfo> mArmedInfo;
-    std::optional<nsecs_t> mLastDispatchTime;
-
-    std::mutex mRunningMutex;
-    std::condition_variable mCv;
-    bool mRunning GUARDED_BY(mRunningMutex) = false;
-};
-
-} // namespace impl
-
 /*
  * VSyncDispatch is a class that will dispatch callbacks relative to system vsync events.
  */
@@ -103,15 +36,7 @@
 public:
     using CallbackToken = StrongTyping<size_t, class CallbackTokenTag, Compare>;
 
-    /* creates a VsyncDispatch.
-     * \param [in]  a timekeeper object for dispatching events.
-     * \param [in]  a tracker object that is monitoring expected vsync events.
-     * \param [in]  a tunable in nanoseconds that indicates when events that fall close together
-     *              should be dispatched in one timer wakeup.
-     */
-    explicit VSyncDispatch(std::unique_ptr<TimeKeeper> tk, VSyncTracker& tracker,
-                           nsecs_t timerSlack);
-    ~VSyncDispatch();
+    virtual ~VSyncDispatch();
 
     /*
      * Registers a callback that will be called at designated points on the vsync timeline.
@@ -126,8 +51,8 @@
      *                          invocation of callbackFn.
      *
      */
-    CallbackToken registerCallback(std::function<void(nsecs_t)> const& callbackFn,
-                                   std::string callbackName);
+    virtual CallbackToken registerCallback(std::function<void(nsecs_t)> const& callbackFn,
+                                           std::string callbackName) = 0;
 
     /*
      * Unregisters a callback.
@@ -135,7 +60,7 @@
      * \param [in] token        The callback to unregister.
      *
      */
-    void unregisterCallback(CallbackToken token);
+    virtual void unregisterCallback(CallbackToken token) = 0;
 
     /*
      * Schedules the registered callback to be dispatched.
@@ -164,7 +89,8 @@
      *                             if a callback was dispatched for the predictedVsync already.
      *                             A ScheduleResult::Error if there was another error.
      */
-    ScheduleResult schedule(CallbackToken token, nsecs_t workDuration, nsecs_t earliestVsync);
+    virtual ScheduleResult schedule(CallbackToken token, nsecs_t workDuration,
+                                    nsecs_t earliestVsync) = 0;
 
     /* Cancels a scheduled callback, if possible.
      *
@@ -173,31 +99,12 @@
      *                      A CancelResult::Cancelled if the callback was successfully cancelled.
      *                      A CancelResult::Error if there was an pre-condition violation.
      */
-    CancelResult cancel(CallbackToken token);
+    virtual CancelResult cancel(CallbackToken token) = 0;
 
-private:
+protected:
+    VSyncDispatch() = default;
     VSyncDispatch(VSyncDispatch const&) = delete;
     VSyncDispatch& operator=(VSyncDispatch const&) = delete;
-
-    using CallbackMap = std::unordered_map<size_t, std::shared_ptr<impl::VSyncDispatchEntry>>;
-
-    void timerCallback();
-    void setTimer(nsecs_t, nsecs_t) REQUIRES(mMutex);
-    void rearmTimer(nsecs_t now) REQUIRES(mMutex);
-    void rearmTimerSkippingUpdateFor(nsecs_t now, CallbackMap::iterator const& skipUpdate)
-            REQUIRES(mMutex);
-    void cancelTimer() REQUIRES(mMutex);
-
-    static constexpr nsecs_t kInvalidTime = std::numeric_limits<int64_t>::max();
-    std::unique_ptr<TimeKeeper> const mTimeKeeper;
-    VSyncTracker& mTracker;
-    nsecs_t const mTimerSlack;
-
-    std::mutex mutable mMutex;
-    size_t mCallbackToken GUARDED_BY(mMutex) = 0;
-
-    CallbackMap mCallbacks GUARDED_BY(mMutex);
-    nsecs_t mIntendedWakeupTime GUARDED_BY(mMutex) = kInvalidTime;
 };
 
 /*
diff --git a/services/surfaceflinger/Scheduler/VSyncDispatch.cpp b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.cpp
similarity index 74%
rename from services/surfaceflinger/Scheduler/VSyncDispatch.cpp
rename to services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.cpp
index c9b2e77..7922484 100644
--- a/services/surfaceflinger/Scheduler/VSyncDispatch.cpp
+++ b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.cpp
@@ -19,65 +19,66 @@
 #include <vector>
 
 #include "TimeKeeper.h"
-#include "VSyncDispatch.h"
+#include "VSyncDispatchTimerQueue.h"
 #include "VSyncTracker.h"
 
 namespace android::scheduler {
 
+VSyncDispatch::~VSyncDispatch() = default;
 VSyncTracker::~VSyncTracker() = default;
 TimeKeeper::~TimeKeeper() = default;
 
-impl::VSyncDispatchEntry::VSyncDispatchEntry(std::string const& name,
-                                             std::function<void(nsecs_t)> const& cb)
+VSyncDispatchTimerQueueEntry::VSyncDispatchTimerQueueEntry(std::string const& name,
+                                                           std::function<void(nsecs_t)> const& cb)
       : mName(name), mCallback(cb), mWorkDuration(0), mEarliestVsync(0) {}
 
-std::optional<nsecs_t> impl::VSyncDispatchEntry::lastExecutedVsyncTarget() const {
+std::optional<nsecs_t> VSyncDispatchTimerQueueEntry::lastExecutedVsyncTarget() const {
     return mLastDispatchTime;
 }
 
-std::string_view impl::VSyncDispatchEntry::name() const {
+std::string_view VSyncDispatchTimerQueueEntry::name() const {
     return mName;
 }
 
-std::optional<nsecs_t> impl::VSyncDispatchEntry::wakeupTime() const {
+std::optional<nsecs_t> VSyncDispatchTimerQueueEntry::wakeupTime() const {
     if (!mArmedInfo) {
         return {};
     }
     return {mArmedInfo->mActualWakeupTime};
 }
 
-nsecs_t impl::VSyncDispatchEntry::schedule(nsecs_t workDuration, nsecs_t earliestVsync,
-                                           VSyncTracker& tracker, nsecs_t now) {
+nsecs_t VSyncDispatchTimerQueueEntry::schedule(nsecs_t workDuration, nsecs_t earliestVsync,
+                                               VSyncTracker& tracker, nsecs_t now) {
     mWorkDuration = workDuration;
     mEarliestVsync = earliestVsync;
     arm(tracker, now);
     return mArmedInfo->mActualWakeupTime;
 }
 
-void impl::VSyncDispatchEntry::update(VSyncTracker& tracker, nsecs_t now) {
+void VSyncDispatchTimerQueueEntry::update(VSyncTracker& tracker, nsecs_t now) {
     if (!mArmedInfo) {
         return;
     }
     arm(tracker, now);
 }
 
-void impl::VSyncDispatchEntry::arm(VSyncTracker& tracker, nsecs_t now) {
+void VSyncDispatchTimerQueueEntry::arm(VSyncTracker& tracker, nsecs_t now) {
     auto const nextVsyncTime =
             tracker.nextAnticipatedVSyncTimeFrom(std::max(mEarliestVsync, now + mWorkDuration));
     mArmedInfo = {nextVsyncTime - mWorkDuration, nextVsyncTime};
 }
 
-void impl::VSyncDispatchEntry::disarm() {
+void VSyncDispatchTimerQueueEntry::disarm() {
     mArmedInfo.reset();
 }
 
-nsecs_t impl::VSyncDispatchEntry::executing() {
+nsecs_t VSyncDispatchTimerQueueEntry::executing() {
     mLastDispatchTime = mArmedInfo->mActualVsyncTime;
     disarm();
     return *mLastDispatchTime;
 }
 
-void impl::VSyncDispatchEntry::callback(nsecs_t t) {
+void VSyncDispatchTimerQueueEntry::callback(nsecs_t t) {
     {
         std::lock_guard<std::mutex> lk(mRunningMutex);
         mRunning = true;
@@ -90,36 +91,37 @@
     mCv.notify_all();
 }
 
-void impl::VSyncDispatchEntry::ensureNotRunning() {
+void VSyncDispatchTimerQueueEntry::ensureNotRunning() {
     std::unique_lock<std::mutex> lk(mRunningMutex);
     mCv.wait(lk, [this]() REQUIRES(mRunningMutex) { return !mRunning; });
 }
 
-VSyncDispatch::VSyncDispatch(std::unique_ptr<TimeKeeper> tk, VSyncTracker& tracker,
-                             nsecs_t timerSlack)
+VSyncDispatchTimerQueue::VSyncDispatchTimerQueue(std::unique_ptr<TimeKeeper> tk,
+                                                 VSyncTracker& tracker, nsecs_t timerSlack)
       : mTimeKeeper(std::move(tk)), mTracker(tracker), mTimerSlack(timerSlack) {}
 
-VSyncDispatch::~VSyncDispatch() {
+VSyncDispatchTimerQueue::~VSyncDispatchTimerQueue() {
     std::lock_guard<decltype(mMutex)> lk(mMutex);
     cancelTimer();
 }
 
-void VSyncDispatch::cancelTimer() {
+void VSyncDispatchTimerQueue::cancelTimer() {
     mIntendedWakeupTime = kInvalidTime;
     mTimeKeeper->alarmCancel();
 }
 
-void VSyncDispatch::setTimer(nsecs_t targetTime, nsecs_t now) {
+void VSyncDispatchTimerQueue::setTimer(nsecs_t targetTime, nsecs_t now) {
     mIntendedWakeupTime = targetTime;
-    mTimeKeeper->alarmIn(std::bind(&VSyncDispatch::timerCallback, this), targetTime - now);
+    mTimeKeeper->alarmIn(std::bind(&VSyncDispatchTimerQueue::timerCallback, this),
+                         targetTime - now);
 }
 
-void VSyncDispatch::rearmTimer(nsecs_t now) {
+void VSyncDispatchTimerQueue::rearmTimer(nsecs_t now) {
     rearmTimerSkippingUpdateFor(now, mCallbacks.end());
 }
 
-void VSyncDispatch::rearmTimerSkippingUpdateFor(nsecs_t now,
-                                                CallbackMap::iterator const& skipUpdateIt) {
+void VSyncDispatchTimerQueue::rearmTimerSkippingUpdateFor(
+        nsecs_t now, CallbackMap::iterator const& skipUpdateIt) {
     std::optional<nsecs_t> min;
     for (auto it = mCallbacks.begin(); it != mCallbacks.end(); it++) {
         auto& callback = it->second;
@@ -143,9 +145,9 @@
     }
 }
 
-void VSyncDispatch::timerCallback() {
+void VSyncDispatchTimerQueue::timerCallback() {
     struct Invocation {
-        std::shared_ptr<impl::VSyncDispatchEntry> callback;
+        std::shared_ptr<VSyncDispatchTimerQueueEntry> callback;
         nsecs_t timestamp;
     };
     std::vector<Invocation> invocations;
@@ -174,18 +176,19 @@
     }
 }
 
-VSyncDispatch::CallbackToken VSyncDispatch::registerCallback(
+VSyncDispatchTimerQueue::CallbackToken VSyncDispatchTimerQueue::registerCallback(
         std::function<void(nsecs_t)> const& callbackFn, std::string callbackName) {
     std::lock_guard<decltype(mMutex)> lk(mMutex);
     return CallbackToken{
             mCallbacks
                     .emplace(++mCallbackToken,
-                             std::make_shared<impl::VSyncDispatchEntry>(callbackName, callbackFn))
+                             std::make_shared<VSyncDispatchTimerQueueEntry>(callbackName,
+                                                                            callbackFn))
                     .first->first};
 }
 
-void VSyncDispatch::unregisterCallback(CallbackToken token) {
-    std::shared_ptr<impl::VSyncDispatchEntry> entry = nullptr;
+void VSyncDispatchTimerQueue::unregisterCallback(CallbackToken token) {
+    std::shared_ptr<VSyncDispatchTimerQueueEntry> entry = nullptr;
     {
         std::lock_guard<decltype(mMutex)> lk(mMutex);
         auto it = mCallbacks.find(token);
@@ -200,8 +203,8 @@
     }
 }
 
-ScheduleResult VSyncDispatch::schedule(CallbackToken token, nsecs_t workDuration,
-                                       nsecs_t earliestVsync) {
+ScheduleResult VSyncDispatchTimerQueue::schedule(CallbackToken token, nsecs_t workDuration,
+                                                 nsecs_t earliestVsync) {
     auto result = ScheduleResult::Error;
     {
         std::lock_guard<decltype(mMutex)> lk(mMutex);
@@ -228,7 +231,7 @@
     return result;
 }
 
-CancelResult VSyncDispatch::cancel(CallbackToken token) {
+CancelResult VSyncDispatchTimerQueue::cancel(CallbackToken token) {
     std::lock_guard<decltype(mMutex)> lk(mMutex);
 
     auto it = mCallbacks.find(token);
diff --git a/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h
new file mode 100644
index 0000000..f058099
--- /dev/null
+++ b/services/surfaceflinger/Scheduler/VSyncDispatchTimerQueue.h
@@ -0,0 +1,130 @@
+/*
+ * Copyright 2019 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 <android-base/thread_annotations.h>
+#include <functional>
+#include <memory>
+#include <mutex>
+#include <string>
+#include <string_view>
+#include <unordered_map>
+
+#include "VSyncDispatch.h"
+
+namespace android::scheduler {
+
+// VSyncDispatchTimerQueueEntry is a helper class representing internal state for each entry in
+// VSyncDispatchTimerQueue hoisted to public for unit testing.
+class VSyncDispatchTimerQueueEntry {
+public:
+    // This is the state of the entry. There are 3 states, armed, running, disarmed.
+    // Valid transition: disarmed -> armed ( when scheduled )
+    // Valid transition: armed -> running -> disarmed ( when timer is called)
+    // Valid transition: armed -> disarmed ( when cancelled )
+    VSyncDispatchTimerQueueEntry(std::string const& name, std::function<void(nsecs_t)> const& fn);
+    std::string_view name() const;
+
+    // Start: functions that are not threadsafe.
+    // Return the last vsync time this callback was invoked.
+    std::optional<nsecs_t> lastExecutedVsyncTarget() const;
+
+    // This moves the state from disarmed->armed and will calculate the wakeupTime.
+    nsecs_t schedule(nsecs_t workDuration, nsecs_t earliestVsync, VSyncTracker& tracker,
+                     nsecs_t now);
+    // This will update armed entries with the latest vsync information. Entry remains armed.
+    void update(VSyncTracker& tracker, nsecs_t now);
+
+    // This will return empty if not armed, or the next calculated wakeup time if armed.
+    // It will not update the wakeupTime.
+    std::optional<nsecs_t> wakeupTime() const;
+
+    // This moves state from armed->disarmed.
+    void disarm();
+
+    // This moves the state from armed->running.
+    // Store the timestamp that this was intended for as the last called timestamp.
+    nsecs_t executing();
+    // End: functions that are not threadsafe.
+
+    // Invoke the callback with the timestamp, moving the state from running->disarmed.
+    void callback(nsecs_t timestamp);
+    // Block calling thread while the callback is executing.
+    void ensureNotRunning();
+
+private:
+    void arm(VSyncTracker& tracker, nsecs_t now);
+    std::string const mName;
+    std::function<void(nsecs_t)> const mCallback;
+
+    nsecs_t mWorkDuration;
+    nsecs_t mEarliestVsync;
+
+    struct ArmingInfo {
+        nsecs_t mActualWakeupTime;
+        nsecs_t mActualVsyncTime;
+    };
+    std::optional<ArmingInfo> mArmedInfo;
+    std::optional<nsecs_t> mLastDispatchTime;
+
+    std::mutex mRunningMutex;
+    std::condition_variable mCv;
+    bool mRunning GUARDED_BY(mRunningMutex) = false;
+};
+
+/*
+ * VSyncDispatchTimerQueue is a class that will dispatch callbacks as per VSyncDispatch interface
+ * using a single timer queue.
+ */
+class VSyncDispatchTimerQueue : public VSyncDispatch {
+public:
+    explicit VSyncDispatchTimerQueue(std::unique_ptr<TimeKeeper> tk, VSyncTracker& tracker,
+                                     nsecs_t timerSlack);
+    ~VSyncDispatchTimerQueue();
+
+    CallbackToken registerCallback(std::function<void(nsecs_t)> const& callbackFn,
+                                   std::string callbackName) final;
+    void unregisterCallback(CallbackToken token) final;
+    ScheduleResult schedule(CallbackToken token, nsecs_t workDuration, nsecs_t earliestVsync) final;
+    CancelResult cancel(CallbackToken token) final;
+
+private:
+    VSyncDispatchTimerQueue(VSyncDispatchTimerQueue const&) = delete;
+    VSyncDispatchTimerQueue& operator=(VSyncDispatchTimerQueue const&) = delete;
+
+    using CallbackMap = std::unordered_map<size_t, std::shared_ptr<VSyncDispatchTimerQueueEntry>>;
+
+    void timerCallback();
+    void setTimer(nsecs_t, nsecs_t) REQUIRES(mMutex);
+    void rearmTimer(nsecs_t now) REQUIRES(mMutex);
+    void rearmTimerSkippingUpdateFor(nsecs_t now, CallbackMap::iterator const& skipUpdate)
+            REQUIRES(mMutex);
+    void cancelTimer() REQUIRES(mMutex);
+
+    static constexpr nsecs_t kInvalidTime = std::numeric_limits<int64_t>::max();
+    std::unique_ptr<TimeKeeper> const mTimeKeeper;
+    VSyncTracker& mTracker;
+    nsecs_t const mTimerSlack;
+
+    std::mutex mutable mMutex;
+    size_t mCallbackToken GUARDED_BY(mMutex) = 0;
+
+    CallbackMap mCallbacks GUARDED_BY(mMutex);
+    nsecs_t mIntendedWakeupTime GUARDED_BY(mMutex) = kInvalidTime;
+};
+
+} // namespace android::scheduler