Allow IdleNotification to trigger Scavenges.

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 4294 matching lines @@
   heap_state.size_of_objects = static_cast<size_t>(SizeOfObjects());
   heap_state.incremental_marking_stopped = incremental_marking()->IsStopped();
   // TODO(ulan): Start incremental marking only for large heaps.
   heap_state.can_start_incremental_marking = true;
   heap_state.sweeping_in_progress =
       mark_compact_collector()->sweeping_in_progress();
   heap_state.mark_compact_speed_in_bytes_per_ms =
       static_cast<size_t>(tracer()->MarkCompactSpeedInBytesPerMillisecond());
   heap_state.incremental_marking_speed_in_bytes_per_ms = static_cast<size_t>(
       tracer()->IncrementalMarkingSpeedInBytesPerMillisecond());
+  heap_state.scavenge_speed_in_bytes_per_ms =
+      static_cast<size_t>(tracer()->ScavengeSpeedInBytesPerMillisecond());
+  heap_state.available_new_space_memory = new_space_.Available();
+  heap_state.new_space_capacity = new_space_.Capacity();
 
   GCIdleTimeAction action =
       gc_idle_time_handler_.Compute(idle_time_in_ms, heap_state);
 
   contexts_disposed_ = 0;
   bool result = false;
   switch (action.type) {
     case DO_INCREMENTAL_MARKING:
       if (incremental_marking()->IsStopped()) {
         incremental_marking()->Start();
       }
       AdvanceIdleIncrementalMarking(action.parameter);
       break;
     case DO_FULL_GC: {
       HistogramTimerScope scope(isolate_->counters()->gc_context());
       const char* message = contexts_disposed_
                                 ? "idle notification: contexts disposed"
                                 : "idle notification: finalize idle round";
       CollectAllGarbage(kReduceMemoryFootprintMask, message);
       gc_idle_time_handler_.NotifyIdleMarkCompact();
       break;
     }
     case DO_SCAVENGE:
       CollectGarbage(NEW_SPACE, "idle notification: scavenge");

[ulan, 2014/09/10 14:25:00]

It just occurred to me that this will trigger scavenge which will increment
scavenges_since_last_idle_round_, which might trigger another idle round. So we
probably want to NotifyIdleScavenge here and decrement
scavenges_since_last_idle_round_.

       break;
     case DO_FINALIZE_SWEEPING:
       mark_compact_collector()->EnsureSweepingCompleted();
       break;
     case DO_NOTHING:
       result = true;
       break;
   }
   if (FLAG_trace_idle_notification) {
     int actual_time_ms = static_cast<int>(timer.Elapsed().InMilliseconds());
@@ skipping 1777 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