Set Android/V8 memory limits from dalvik.vm.heapsize.

webkit/glue/webkitplatformsupport_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "webkit/glue/webkitplatformsupport_impl.h"
 
 #if defined(OS_LINUX)
 #include <malloc.h>
 #endif
 
 #include <math.h>
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "base/memory/singleton.h"
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/stats_counters.h"
 #include "base/platform_file.h"
 #include "base/process_util.h"
 #include "base/rand_util.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/synchronization/lock.h"
+#include "base/sys_info.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "grit/webkit_chromium_resources.h"
 #include "grit/webkit_resources.h"
 #include "grit/webkit_strings.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebCookie.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebData.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrameClient.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPluginListBuilder.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebScreenInfo.h"
@@ skipping 576 matching lines @@
   return 0;
 }
 
 WebKit::WebString WebKitPlatformSupportImpl::signedPublicKeyAndChallengeString(
     unsigned key_size_index,
     const WebKit::WebString& challenge,
     const WebKit::WebURL& url) {
   return WebKit::WebString("");
 }
 
-#if defined(OS_LINUX)
-static size_t memoryUsageMBLinux() {
+#if defined(OS_LINUX) || defined(OS_ANDROID)
+static size_t memoryUsageMB() {
   struct mallinfo minfo = mallinfo();
   uint64_t mem_usage =
 #if defined(USE_TCMALLOC)
       minfo.uordblks
 #else
       (minfo.hblkhd + minfo.arena)
 #endif
       >> 20;
 
   v8::HeapStatistics stat;
   v8::V8::GetHeapStatistics(&stat);
   return mem_usage + (static_cast<uint64_t>(stat.total_heap_size()) >> 20);
 }
-#endif
-
-#if defined(OS_MACOSX)
-static size_t memoryUsageMBMac() {
+#elif defined(OS_MACOSX)
+static size_t memoryUsageMB() {
   using base::ProcessMetrics;
   static ProcessMetrics* process_metrics =
       // The default port provider is sufficient to get data for the current
       // process.
       ProcessMetrics::CreateProcessMetrics(base::GetCurrentProcessHandle(),
                                            NULL);
   DCHECK(process_metrics);
   return process_metrics->GetWorkingSetSize() >> 20;
 }
-#endif
-
-#if !defined(OS_LINUX) && !defined(OS_MACOSX)
-static size_t memoryUsageMBGeneric() {
+#else
+static size_t memoryUsageMB() {
   using base::ProcessMetrics;
   static ProcessMetrics* process_metrics =
       ProcessMetrics::CreateProcessMetrics(base::GetCurrentProcessHandle());
   DCHECK(process_metrics);
   return process_metrics->GetPagefileUsage() >> 20;
 }
 #endif
 
 static size_t getMemoryUsageMB(bool bypass_cache) {
   size_t current_mem_usage = 0;
   MemoryUsageCache* mem_usage_cache_singleton = MemoryUsageCache::GetInstance();
   if (!bypass_cache &&
       mem_usage_cache_singleton->IsCachedValueValid(&current_mem_usage))
     return current_mem_usage;
 
-  current_mem_usage =
-#if defined(OS_LINUX)
-      memoryUsageMBLinux();
-#elif defined(OS_MACOSX)
-      memoryUsageMBMac();
-#else
-      memoryUsageMBGeneric();
-#endif
+  current_mem_usage = memoryUsageMB();
   mem_usage_cache_singleton->SetMemoryValue(current_mem_usage);
   return current_mem_usage;
 }
 
 size_t WebKitPlatformSupportImpl::memoryUsageMB() {
   return getMemoryUsageMB(false);
 }
 
 size_t WebKitPlatformSupportImpl::actualMemoryUsageMB() {
   return getMemoryUsageMB(true);
 }
 
+#if defined(OS_ANDROID)
+size_t WebKitPlatformSupportImpl::lowMemoryUsageMB() {
+  // If memory usage is below this threshold, do not bother forcing GC.
+  // Allow us to use up to our memory class value before V8's GC kicks in.
+  // These values have been determined by experimentation.
+  return base::SysInfo::DalvikHeapSizeMB() / 4;

[Xianzhu, 2012/05/15 17:18:03]

This seems too conservative. We ever used the dalvik heap size (got from Java
ActivityManager.getLargeMemoryClass() which is also the value of system property
dalvik.vm.heapsize) as the return value of lowMemoryUsageMB(), and 1.5 time of
it as the return value of highMemoryUsageMB().

As discussed with klobag@ and vegorov@ yesterday, V8::LowMemoryNotification
should be only called when the process meets critical memory condition. Too
small return values of these functions will result to many unnecessary expensive
V8::LowMemoryNotification calls.

[Xianzhu, 2012/05/15 17:53:23]

After further testing, I found that the change about memoryUsageMB() (which is
now about 1/5 of the original memoryUsageMBGeneric()) made these values not that
conservative. Now the values look good to me and I'd discuss internally for
further optimization of them.

+}
+
+size_t WebKitPlatformSupportImpl::highMemoryUsageMB() {
+  // If memory usage is above this threshold, force GC more aggressively.
+  return lowMemoryUsageMB() * 2;
+}
+
+size_t WebKitPlatformSupportImpl::highUsageDeltaMB() {
+  // Threshold of delta of memory usage growth (vs. last working set estimate)
+  // to force GC when memory usage is high.
+  // Avoid constant V8 GC when memory usage equals to working set estimate.
+  return lowMemoryUsageMB() / 2;
+}
+#endif
+
 void WebKitPlatformSupportImpl::SuspendSharedTimer() {
   ++shared_timer_suspended_;
 }
 
 void WebKitPlatformSupportImpl::ResumeSharedTimer() {
   // The shared timer may have fired or been adjusted while we were suspended.
   if (--shared_timer_suspended_ == 0 && !shared_timer_.IsRunning()) {
     setSharedTimerFireInterval(
         shared_timer_fire_time_ - monotonicallyIncreasingTime());
   }
@@ skipping 12 matching lines @@
   worker_task_runner->OnWorkerRunLoopStarted(runLoop);
 }
 
 void WebKitPlatformSupportImpl::didStopWorkerRunLoop(
     const WebKit::WebWorkerRunLoop& runLoop) {
   WorkerTaskRunner* worker_task_runner = WorkerTaskRunner::Instance();
   worker_task_runner->OnWorkerRunLoopStopped(runLoop);
 }
 
 }  // namespace webkit_glue