Merge "Add optimizations to keep TaskPersister queue small." into lmp-dev (941aa1af) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/am/TaskPersister.java

+51 −8

Original line number	Diff line number	Diff line
		@@ -51,6 +51,12 @@ public class TaskPersister {
		* task being launched a chance to load its resources without this occupying IO bandwidth. */
		private static final long PRE_TASK_DELAY_MS = 3000;

		/** The maximum number of entries to keep in the queue before draining it automatically. */
		private static final int MAX_WRITE_QUEUE_LENGTH = 6;

		/** Special value for mWriteTime to mean don't wait, just write */
		private static final long FLUSH_QUEUE = -1;

		private static final String RECENTS_FILENAME = "_task";
		private static final String TASKS_DIRNAME = "recent_tasks";
		private static final String TASK_EXTENSION = ".xml";
		@@ -120,6 +126,31 @@ public class TaskPersister {
		mLazyTaskWriterThread.start();
		}

		private void removeThumbnails(TaskRecord task) {
		final String taskString = Integer.toString(task.taskId);
		for (int queueNdx = mWriteQueue.size() - 1; queueNdx >= 0; --queueNdx) {
		final WriteQueueItem item = mWriteQueue.get(queueNdx);
		if (item instanceof ImageWriteQueueItem &&
		((ImageWriteQueueItem) item).mFilename.startsWith(taskString)) {
		if (DEBUG) Slog.d(TAG, "Removing " + ((ImageWriteQueueItem) item).mFilename +
		" from write queue");
		mWriteQueue.remove(queueNdx);
		}
		}
		}

		private void yieldIfQueueTooDeep() {
		boolean stall = false;
		synchronized (this) {
		if (mNextWriteTime == FLUSH_QUEUE) {
		stall = true;
		}
		}
		if (stall) {
		Thread.yield();
		}
		}

		void wakeup(TaskRecord task, boolean flush) {
		synchronized (this) {
		if (task != null) {
		@@ -128,6 +159,10 @@ public class TaskPersister {
		final WriteQueueItem item = mWriteQueue.get(queueNdx);
		if (item instanceof TaskWriteQueueItem &&
		((TaskWriteQueueItem) item).mTask == task) {
		if (!task.inRecents) {
		// This task is being removed.
		removeThumbnails(task);
		}
		break;
		}
		}
		@@ -138,15 +173,18 @@ public class TaskPersister {
		// Dummy.
		mWriteQueue.add(new WriteQueueItem());
		}
		if (flush) {
		mNextWriteTime = -1;
		if (flush \|\| mWriteQueue.size() > MAX_WRITE_QUEUE_LENGTH) {
		mNextWriteTime = FLUSH_QUEUE;
		} else if (mNextWriteTime == 0) {
		mNextWriteTime = SystemClock.uptimeMillis() + PRE_TASK_DELAY_MS;
		}
		if (DEBUG) Slog.d(TAG, "wakeup: task=" + task + " flush=" + flush + " mNextWriteTime="
		+ mNextWriteTime + " Callers=" + Debug.getCallers(4));
		+ mNextWriteTime + " mWriteQueue.size=" + mWriteQueue.size()
		+ " Callers=" + Debug.getCallers(4));
		notifyAll();
		}

		yieldIfQueueTooDeep();
		}

		void saveImage(Bitmap image, String filename) {
		@@ -166,7 +204,9 @@ public class TaskPersister {
		if (queueNdx < 0) {
		mWriteQueue.add(new ImageWriteQueueItem(filename, image));
		}
		if (mNextWriteTime == 0) {
		if (mWriteQueue.size() > MAX_WRITE_QUEUE_LENGTH) {
		mNextWriteTime = FLUSH_QUEUE;
		} else if (mNextWriteTime == 0) {
		mNextWriteTime = SystemClock.uptimeMillis() + PRE_TASK_DELAY_MS;
		}
		if (DEBUG) Slog.d(TAG, "saveImage: filename=" + filename + " now=" +
		@@ -174,6 +214,8 @@ public class TaskPersister {
		mNextWriteTime + " Callers=" + Debug.getCallers(4));
		notifyAll();
		}

		yieldIfQueueTooDeep();
		}

		Bitmap getThumbnail(String filename) {
		@@ -425,7 +467,7 @@ public class TaskPersister {
		// If mNextWriteTime, then don't delay between each call to saveToXml().
		final WriteQueueItem item;
		synchronized (TaskPersister.this) {
		if (mNextWriteTime >= 0) {
		if (mNextWriteTime != FLUSH_QUEUE) {
		// The next write we don't have to wait so long.
		mNextWriteTime = SystemClock.uptimeMillis() + INTER_WRITE_DELAY_MS;
		if (DEBUG) Slog.d(TAG, "Next write time may be in " +
		@@ -439,13 +481,14 @@ public class TaskPersister {
		TaskPersister.this.wait();
		} catch (InterruptedException e) {
		}
		// Invariant: mNextWriteTime is either -1 or PRE_WRITE_DELAY_MS from now.
		// Invariant: mNextWriteTime is either FLUSH_QUEUE or PRE_WRITE_DELAY_MS
		// from now.
		}
		item = mWriteQueue.remove(0);

		long now = SystemClock.uptimeMillis();
		if (DEBUG) Slog.d(TAG, "LazyTaskWriter: now=" + now + " mNextWriteTime=" +
		mNextWriteTime);
		mNextWriteTime + " mWriteQueue.size=" + mWriteQueue.size());
		while (now < mNextWriteTime) {
		try {
		if (DEBUG) Slog.d(TAG, "LazyTaskWriter: waiting " +
		@@ -484,7 +527,7 @@ public class TaskPersister {
		TaskRecord task = ((TaskWriteQueueItem) item).mTask;
		if (DEBUG) Slog.d(TAG, "Writing task=" + task);
		synchronized (mService) {
		if (mService.mRecentTasks.contains(task)) {
		if (task.inRecents) {
		// Still there.
		try {
		if (DEBUG) Slog.d(TAG, "Saving task=" + task);