commit 5d2a3f7bdd23003af78e3f09e96b9f77ff33c4b6
author Mathieu Chartier <mathieuc@google.com> Wed May 11 11:35:39 2016 -0700
committer Mathieu Chartier <mathieuc@google.com> Wed May 11 14:30:17 2016 -0700
tree b4acc13230922ddf87b8d99341d1f8e376cd0031
parent d6f374071804b3efe864f16d75fa22cb9971ed5a

Add histogram for native allocations

Shows up in traces.txt, sample output:
Histogram of native allocation 0:4315,131072:33,1179648:3 bucket size 131072
Histogram of native free 0:995,131072:19,1179648:2 bucket size 131072

Bug: 28680116

(cherry picked from commit 0dce75dc6945c221a054eb9c479fb60efd193719)

Change-Id: Iaa07c6b8da0d6bab64a8fd4af8a02fc0b8c70e9e

runtime/gc/heap.cc

diff --git a/runtime/gc/heap.cc b/runtime/gc/heap.cc
index df5aa0a..fa540c0 100644
--- a/runtime/gc/heap.cc
+++ b/runtime/gc/heap.cc
@@ -119,6 +119,8 @@
 // Dump the rosalloc stats on SIGQUIT.
 static constexpr bool kDumpRosAllocStatsOnSigQuit = false;
 
+static constexpr size_t kNativeAllocationHistogramBuckets = 16;
+
 static inline bool CareAboutPauseTimes() {
   return Runtime::Current()->InJankPerceptibleProcessState();
 }
@@ -186,6 +188,11 @@
       total_objects_freed_ever_(0),
       num_bytes_allocated_(0),
       native_bytes_allocated_(0),
+      native_histogram_lock_("Native allocation lock"),
+      native_allocation_histogram_("Native allocation sizes",
+                                   1U,
+                                   kNativeAllocationHistogramBuckets),
+      native_free_histogram_("Native free sizes", 1U, kNativeAllocationHistogramBuckets),
       num_bytes_freed_revoke_(0),
       verify_missing_card_marks_(false),
       verify_system_weaks_(false),
@@ -1185,6 +1192,20 @@
     rosalloc_space_->DumpStats(os);
   }
 
+  {
+    MutexLock mu(Thread::Current(), native_histogram_lock_);
+    if (native_allocation_histogram_.SampleSize() > 0u) {
+      os << "Histogram of native allocation ";
+      native_allocation_histogram_.DumpBins(os);
+      os << " bucket size " << native_allocation_histogram_.BucketWidth() << "\n";
+    }
+    if (native_free_histogram_.SampleSize() > 0u) {
+      os << "Histogram of native free ";
+      native_free_histogram_.DumpBins(os);
+      os << " bucket size " << native_free_histogram_.BucketWidth() << "\n";
+    }
+  }
+
   BaseMutex::DumpAll(os);
 }
 
@@ -3848,6 +3869,10 @@
 
 void Heap::RegisterNativeAllocation(JNIEnv* env, size_t bytes) {
   Thread* self = ThreadForEnv(env);
+  {
+    MutexLock mu(self, native_histogram_lock_);
+    native_allocation_histogram_.AddValue(bytes);
+  }
   if (native_need_to_run_finalization_) {
     RunFinalization(env, kNativeAllocationFinalizeTimeout);
     UpdateMaxNativeFootprint();
@@ -3892,6 +3917,10 @@
 
 void Heap::RegisterNativeFree(JNIEnv* env, size_t bytes) {
   size_t expected_size;
+  {
+    MutexLock mu(Thread::Current(), native_histogram_lock_);
+    native_free_histogram_.AddValue(bytes);
+  }
   do {
     expected_size = native_bytes_allocated_.LoadRelaxed();
     if (UNLIKELY(bytes > expected_size)) {