Keeping only running users recents in memory
Currently, all the users' recent tasks are loaded into memory and kept
in sync with the persistent storage. This changes the system so
that it loads a users recents into memory lazily (i.e. when
getRecentTasks is called for that user) and unloads them from the
memory as soon as the user is stopped. This also required bucketizing
the taskIds per user, so that the next available taskId can be assigned
without having knowledge of all the tasks that are stored away in
persistent storage but are not available in memory.
Bug-Id: b/24569398
Change-Id: Ia5cb64d9f4ee727225dce34e45ca63e946ac27a8
diff --git a/services/core/java/com/android/server/am/TaskPersister.java b/services/core/java/com/android/server/am/TaskPersister.java
index 9a00075..283939e 100644
--- a/services/core/java/com/android/server/am/TaskPersister.java
+++ b/services/core/java/com/android/server/am/TaskPersister.java
@@ -21,16 +21,18 @@
import android.os.Debug;
import android.os.Environment;
import android.os.FileUtils;
+import android.os.Process;
import android.os.SystemClock;
import android.util.ArraySet;
import android.util.AtomicFile;
import android.util.Slog;
import android.util.Xml;
-import android.os.Process;
import com.android.internal.util.FastXmlSerializer;
import com.android.internal.util.XmlUtils;
+import libcore.io.IoUtils;
+
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlSerializer;
@@ -42,12 +44,10 @@
import java.io.IOException;
import java.io.StringWriter;
import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
import java.util.Comparator;
import java.util.List;
-import libcore.io.IoUtils;
-
public class TaskPersister {
static final String TAG = "TaskPersister";
static final boolean DEBUG = false;
@@ -113,7 +113,7 @@
ArrayList<WriteQueueItem> mWriteQueue = new ArrayList<WriteQueueItem>();
TaskPersister(File systemDir, ActivityStackSupervisor stackSupervisor,
- RecentTasks recentTasks) {
+ ActivityManagerService service, RecentTasks recentTasks) {
final File legacyImagesDir = new File(systemDir, IMAGES_DIRNAME);
if (legacyImagesDir.exists()) {
@@ -130,7 +130,7 @@
}
mStackSupervisor = stackSupervisor;
- mService = stackSupervisor.mService;
+ mService = service;
mRecentTasks = recentTasks;
mLazyTaskWriterThread = new LazyTaskWriterThread("LazyTaskWriterThread");
}
@@ -145,11 +145,15 @@
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).mFilePath.startsWith(taskString)) {
- if (DEBUG) Slog.d(TAG, "Removing " + ((ImageWriteQueueItem) item).mFilePath +
- " from write queue");
- mWriteQueue.remove(queueNdx);
+ if (item instanceof ImageWriteQueueItem) {
+ final File thumbnailFile = new File(((ImageWriteQueueItem) item).mFilePath);
+ if (thumbnailFile.getName().startsWith(taskString)) {
+ if (DEBUG) {
+ Slog.d(TAG, "Removing " + ((ImageWriteQueueItem) item).mFilePath +
+ " from write queue");
+ }
+ mWriteQueue.remove(queueNdx);
+ }
}
}
}
@@ -185,7 +189,8 @@
mWriteQueue.add(new TaskWriteQueueItem(task));
}
} else {
- // Dummy.
+ // Dummy. Ensures removeObsoleteFiles is called when LazyTaskThreadWriter is
+ // notified.
mWriteQueue.add(new WriteQueueItem());
}
if (flush || mWriteQueue.size() > MAX_WRITE_QUEUE_LENGTH) {
@@ -323,8 +328,8 @@
return null;
}
- private List<TaskRecord> restoreTasksForUserLocked(final int userId) {
- final List<TaskRecord> tasks = new ArrayList<TaskRecord>();
+ List<TaskRecord> restoreTasksForUserLocked(final int userId) {
+ final ArrayList<TaskRecord> tasks = new ArrayList<TaskRecord>();
ArraySet<Integer> recoveredTaskIds = new ArraySet<Integer>();
File userTasksDir = getUserTasksDir(userId);
@@ -351,10 +356,10 @@
event != XmlPullParser.END_TAG) {
final String name = in.getName();
if (event == XmlPullParser.START_TAG) {
- if (DEBUG) Slog.d(TAG, "restoreTasksLocked: START_TAG name=" + name);
+ if (DEBUG) Slog.d(TAG, "restoreTasksForUserLocked: START_TAG name=" + name);
if (TAG_TASK.equals(name)) {
final TaskRecord task = TaskRecord.restoreFromXml(in, mStackSupervisor);
- if (DEBUG) Slog.d(TAG, "restoreTasksLocked: restored task="
+ if (DEBUG) Slog.d(TAG, "restoreTasksForUserLocked: restored task="
+ task);
if (task != null) {
// XXX Don't add to write queue... there is no reason to write
@@ -362,7 +367,7 @@
// read the same thing again.
// mWriteQueue.add(new TaskWriteQueueItem(task));
final int taskId = task.taskId;
- mStackSupervisor.setNextTaskId(taskId);
+ mStackSupervisor.setNextTaskIdForUserLocked(taskId, userId);
// Check if it's a valid user id. Don't add tasks for removed users.
if (userId == task.userId) {
task.isPersistable = true;
@@ -396,15 +401,6 @@
if (!DEBUG) {
removeObsoleteFiles(recoveredTaskIds, userTasksDir.listFiles());
}
- return tasks;
- }
-
- ArrayList<TaskRecord> restoreTasksLocked(final int[] validUserIds) {
- final ArrayList<TaskRecord> tasks = new ArrayList<TaskRecord>();
-
- for (int userId : validUserIds) {
- tasks.addAll(restoreTasksForUserLocked(userId));
- }
// Fix up task affiliation from taskIds
for (int taskNdx = tasks.size() - 1; taskNdx >= 0; --taskNdx) {
@@ -413,9 +409,7 @@
task.setNextAffiliate(taskIdToTask(task.mNextAffiliateTaskId, tasks));
}
- TaskRecord[] tasksArray = new TaskRecord[tasks.size()];
- tasks.toArray(tasksArray);
- Arrays.sort(tasksArray, new Comparator<TaskRecord>() {
+ Collections.sort(tasks, new Comparator<TaskRecord>() {
@Override
public int compare(TaskRecord lhs, TaskRecord rhs) {
final long diff = rhs.mLastTimeMoved - lhs.mLastTimeMoved;
@@ -428,8 +422,7 @@
}
}
});
-
- return new ArrayList<TaskRecord>(Arrays.asList(tasksArray));
+ return tasks;
}
private static void removeObsoleteFiles(ArraySet<Integer> persistentTaskIds, File[] files) {
@@ -462,7 +455,13 @@
}
private void removeObsoleteFiles(ArraySet<Integer> persistentTaskIds) {
- for (int userId : mService.getRunningUserIds()) {
+ int[] candidateUserIds;
+ synchronized (mService) {
+ // Remove only from directories of the users who have recents in memory synchronized
+ // with persistent storage.
+ candidateUserIds = mRecentTasks.usersWithRecentsLoadedLocked();
+ }
+ for (int userId : candidateUserIds) {
removeObsoleteFiles(persistentTaskIds, getUserImagesDir(userId).listFiles());
removeObsoleteFiles(persistentTaskIds, getUserTasksDir(userId).listFiles());
}