commit d288a266723e18d846ea1215919f7a377504225b
author Mathieu Chartier <mathieuc@google.com> Fri Jul 10 13:44:42 2015 -0700
committer Mathieu Chartier <mathieuc@google.com> Fri Jul 10 15:33:59 2015 -0700
tree c14eeb372207ec9b688a737d5b708b4f9c82d7b0
parent 07e1c409acc375ae88b6cc73fe4541db529c9638

Change conditionallyCheckInstanceCounts to use countInstancesOfClasses

countInstancesOfClasses allows passing multiple classes unlike
countInstanceOfClass. This provides a speedup since we dont traverse
the heap multiple times.

Changed ActivityThread.dumpMemInfo to do a GC since countInstancesOfClass
no longer does GC before counting.

https://code.google.com/p/android/issues/detail?id=177552

Change-Id: Ia85684f40cf59a52aa71a8479c711a994651209b

core/java/android/app/ActivityThread.java

diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index 9449eff..0d71ea3 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -973,7 +973,7 @@
             long nativeFree = Debug.getNativeHeapFreeSize() / 1024;
 
             Runtime runtime = Runtime.getRuntime();
-
+            runtime.gc();  // Do GC since countInstancesOfClass counts unreachable objects.
             long dalvikMax = runtime.totalMemory() / 1024;
             long dalvikFree = runtime.freeMemory() / 1024;
             long dalvikAllocated = dalvikMax - dalvikFree;

core/java/android/os/StrictMode.java

diff --git a/core/java/android/os/StrictMode.java b/core/java/android/os/StrictMode.java
index 5018711..44f4ab1 100644
--- a/core/java/android/os/StrictMode.java
+++ b/core/java/android/os/StrictMode.java
@@ -1520,7 +1520,8 @@
      */
     public static void conditionallyCheckInstanceCounts() {
         VmPolicy policy = getVmPolicy();
-        if (policy.classInstanceLimit.size() == 0) {
+        int policySize = policy.classInstanceLimit.size();
+        if (policySize == 0) {
             return;
         }
 
@@ -1529,15 +1530,17 @@
         System.gc();
 
         // Note: classInstanceLimit is immutable, so this is lock-free
-        for (Map.Entry<Class, Integer> entry : policy.classInstanceLimit.entrySet()) {
-            Class klass = entry.getKey();
-            int limit = entry.getValue();
-            long instances = VMDebug.countInstancesOfClass(klass, false);
-            if (instances <= limit) {
-                continue;
+        // Create the classes array.
+        Class[] classes = policy.classInstanceLimit.keySet().toArray(new Class[policySize]);
+        long[] instanceCounts = VMDebug.countInstancesOfClasses(classes, false);
+        for (int i = 0; i < classes.length; ++i) {
+            Class klass = classes[i];
+            int limit = policy.classInstanceLimit.get(klass);
+            long instances = instanceCounts[i];
+            if (instances > limit) {
+                Throwable tr = new InstanceCountViolation(klass, instances, limit);
+                onVmPolicyViolation(tr.getMessage(), tr);
             }
-            Throwable tr = new InstanceCountViolation(klass, instances, limit);
-            onVmPolicyViolation(tr.getMessage(), tr);
         }
     }