Bug 1075644 - Reduce Gecko thread priority at very start; r=snorp r=bnicholson

mobile/android/base/GeckoApp.java

@@ -1254,6 +1254,11 @@ public abstract class GeckoApp
             }, 1000 * 5 /* 5 seconds */);
         }
 
+        // Heavy load on the Gecko thread can slow down the time it takes for UI to appear on
+        // single-core devices. By minimizing the Gecko thread priority, we ensure that the UI
+        // appears quickly. The priority is reset to normal once thumbnails are loaded.
+        ThreadUtils.reduceGeckoPriority();
+
         Bundle stateBundle = getIntent().getBundleExtra(EXTRA_STATE_BUNDLE);
         if (stateBundle != null) {
             // Use the state bundle if it was given as an intent extra. This is
@@ -1630,6 +1635,10 @@ public abstract class GeckoApp
         } else if (NotificationHelper.HELPER_BROADCAST_ACTION.equals(action)) {
             NotificationHelper.getInstance(getApplicationContext()).handleNotificationIntent(intent);
         }
+
+        // Reset Gecko to normal priority. We may reduce the
+        // priority again later, e.g. for loading thumbnails.
+        ThreadUtils.resetGeckoPriority();
     }
 
     private String restoreSessionTabs(final boolean isExternalURL) throws SessionRestoreException {

mobile/android/base/GeckoThread.java

@@ -51,6 +51,7 @@ public class GeckoThread extends Thread implements GeckoEventListener {
         if (isCreated())
             return false;
         sGeckoThread = new GeckoThread(sArgs, sAction, sUri);
+        ThreadUtils.sGeckoThread = sGeckoThread;
         return true;
     }
 
@@ -164,7 +165,6 @@ public class GeckoThread extends Thread implements GeckoEventListener {
     @Override
     public void run() {
         Looper.prepare();
-        ThreadUtils.sGeckoThread = this;
         ThreadUtils.sGeckoHandler = new Handler();
         ThreadUtils.sGeckoQueue = Looper.myQueue();
 

mobile/android/base/home/TopSitesPanel.java

@@ -98,9 +98,6 @@ public class TopSitesPanel extends HomeFragment {
     // Max number of entries shown in the grid from the cursor.
     private int mMaxGridEntries;
 
-    // Time in ms until the Gecko thread is reset to normal priority.
-    private static final long PRIORITY_RESET_TIMEOUT = 10000;
-
     public static TopSitesPanel newInstance() {
         return new TopSitesPanel();
     }
@@ -347,7 +344,7 @@ public class TopSitesPanel extends HomeFragment {
         // appear, especially during startup (bug 897162). By minimizing the
         // Gecko thread priority, we ensure that the UI appears quickly. The
         // priority is reset to normal once thumbnails are loaded.
-        ThreadUtils.reduceGeckoPriority(PRIORITY_RESET_TIMEOUT);
+        ThreadUtils.reduceGeckoPriority();
     }
 
     /**

mobile/android/base/util/ThreadUtils.java

@@ -17,6 +17,9 @@ import android.util.Log;
 public final class ThreadUtils {
     private static final String LOGTAG = "ThreadUtils";
 
+    // Time in ms until the Gecko thread is reset to normal priority.
+    private static final long PRIORITY_RESET_TIMEOUT = 10000;
+
     /**
      * Controls the action taken when a method like
      * {@link ThreadUtils#assertOnUiThread(AssertBehavior)} detects a problem.
@@ -209,10 +212,8 @@ public final class ThreadUtils {
      *
      * Note that there are no guards in place to prevent multiple calls
      * to this method from conflicting with each other.
-     *
-     * @param timeout Timeout in ms after which the priority will be reset
      */
-    public static void reduceGeckoPriority(long timeout) {
+    public static void reduceGeckoPriority() {
         if (Runtime.getRuntime().availableProcessors() > 1) {
             // Don't reduce priority for multicore devices. We use availableProcessors()
             // for its fast performance. It may give false negatives (i.e. multicore
@@ -222,7 +223,7 @@ public final class ThreadUtils {
         if (!sIsGeckoPriorityReduced && sGeckoThread != null) {
             sIsGeckoPriorityReduced = true;
             sGeckoThread.setPriority(Thread.MIN_PRIORITY);
-            getUiHandler().postDelayed(sPriorityResetRunnable, timeout);
+            getUiHandler().postDelayed(sPriorityResetRunnable, PRIORITY_RESET_TIMEOUT);
         }
     }