Add mode to reduce memory usage in idle notification.

src/heap/heap.cc

 // Copyright 2012 the V8 project 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 "src/v8.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/base/bits.h"
 #include "src/base/once.h"
@@ skipping 889 matching lines @@
           (collector == SCAVENGER) ? isolate_->counters()->gc_scavenger()
                                    : isolate_->counters()->gc_compactor());
       next_gc_likely_to_collect_more =
           PerformGarbageCollection(collector, gc_callback_flags);
     }
 
     GarbageCollectionEpilogue();
     if (collector == MARK_COMPACTOR && FLAG_track_detached_contexts) {
       isolate()->CheckDetachedContextsAfterGC();
     }
+
+    if (collector == MARK_COMPACTOR) {
+      gc_idle_time_handler_.NotifyMarkCompact();
+    } else {
+      gc_idle_time_handler_.NotifyScavenge();
+    }
+
     tracer()->Stop(collector);
   }
 
   // Start incremental marking for the next cycle. The heap snapshot
   // generator needs incremental marking to stay off after it aborted.
   if (!mark_compact_collector()->abort_incremental_marking() &&
       incremental_marking()->IsStopped() &&
       incremental_marking()->ShouldActivateEvenWithoutIdleNotification()) {
     incremental_marking()->Start();
   }
@@ skipping 707 matching lines @@
   new_space_.LowerInlineAllocationLimit(
       new_space_.inline_allocation_limit_step());
 
   // Update how much has survived scavenge.
   IncrementYoungSurvivorsCounter(static_cast<int>(
       (PromotedSpaceSizeOfObjects() - survived_watermark) + new_space_.Size()));
 
   LOG(isolate_, ResourceEvent("scavenge", "end"));
 
   gc_state_ = NOT_IN_GC;
-
-  gc_idle_time_handler_.NotifyScavenge();
 }
 
 
 String* Heap::UpdateNewSpaceReferenceInExternalStringTableEntry(Heap* heap,
                                                                 Object** p) {
   MapWord first_word = HeapObject::cast(*p)->map_word();
 
   if (!first_word.IsForwardingAddress()) {
     // Unreachable external string can be finalized.
     heap->FinalizeExternalString(String::cast(*p));
@@ skipping 2906 matching lines @@
             static_cast<size_t>(idle_time_in_ms))))) {
     OverApproximateWeakClosure(
         "Idle notification: overapproximate weak closure");
     return true;
   } else if (incremental_marking()->IsComplete() ||
              (mark_compact_collector_.marking_deque()->IsEmpty() &&
               gc_idle_time_handler_.ShouldDoFinalIncrementalMarkCompact(
                   static_cast<size_t>(idle_time_in_ms), size_of_objects,
                   final_incremental_mark_compact_speed_in_bytes_per_ms))) {
     CollectAllGarbage(kNoGCFlags, "idle notification: finalize incremental");
+    gc_idle_time_handler_.NotifyIdleMarkCompact();
     ReduceNewSpaceSize(is_long_idle_notification);
     return true;
   }
   return false;
 }
 
 
 static double MonotonicallyIncreasingTimeInMs() {
   return V8::GetCurrentPlatform()->MonotonicallyIncreasingTime() *
          static_cast<double>(base::Time::kMillisecondsPerSecond);
@@ skipping 59 matching lines @@
       gc_idle_time_handler_.Compute(idle_time_in_ms, heap_state);
   isolate()->counters()->gc_idle_time_allotted_in_ms()->AddSample(
       static_cast<int>(idle_time_in_ms));
 
   bool result = false;
   switch (action.type) {
     case DONE:
       result = true;
       break;
     case DO_INCREMENTAL_MARKING: {
       if (incremental_marking()->IsStopped()) {

[Hannes Payer (out of office), 2015/05/04 11:20:37]

please add a TODO that start should take reduce_memory of DO_INCREMENTAL_MARKING
into account

[ulan, 2015/05/05 12:10:13]

Done.

         incremental_marking()->Start();
       }
       double remaining_idle_time_in_ms = 0.0;
       do {
         incremental_marking()->Step(
             action.parameter, IncrementalMarking::NO_GC_VIA_STACK_GUARD,
             IncrementalMarking::FORCE_MARKING,
             IncrementalMarking::DO_NOT_FORCE_COMPLETION);
         remaining_idle_time_in_ms =
             deadline_in_ms - MonotonicallyIncreasingTimeInMs();
@@ skipping 1759 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   CODE_AGE_LIST_COMPLETE(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   MemCopy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   MemCopy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 }
 }  // namespace v8::internal