Reduce new space size during idle times only in memory mode after scavenge, full gc, or finalized i…

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 4546 matching lines @@
   DCHECK(AllowHeapAllocation::IsAllowed());
   if (!IsHeapIterable()) {
     CollectAllGarbage(kMakeHeapIterableMask, "Heap::MakeHeapIterable");
   }
   if (mark_compact_collector()->sweeping_in_progress()) {
     mark_compact_collector()->EnsureSweepingCompleted();
   }
   DCHECK(IsHeapIterable());
 }
 
+
+void Heap::ReduceNewSpaceSize(GCIdleTimeAction action) {
+  if (action.reduce_memory &&
+      (action.type == DO_SCAVENGE || action.type == DO_FULL_GC ||

[ulan, 2015/05/21 12:29:31]

what about DO_NOTHING and DONE?

[Hannes Payer (out of office), 2015/05/21 12:31:08]

I think it just makes sense after an actual GC, because new space got evacuated.

+       (action.type == DO_INCREMENTAL_MARKING &&
+        incremental_marking()->IsStopped()))) {
+    new_space_.Shrink();
+    UncommitFromSpace();
+  }
+}
+
+
 bool Heap::TryFinalizeIdleIncrementalMarking(
     double idle_time_in_ms, size_t size_of_objects,
     size_t final_incremental_mark_compact_speed_in_bytes_per_ms) {
   if (FLAG_overapproximate_weak_closure &&
       (incremental_marking()->IsReadyToOverApproximateWeakClosure() ||
        (!incremental_marking()->weak_closure_was_overapproximated() &&
         mark_compact_collector_.marking_deque()->IsEmpty() &&
         gc_idle_time_handler_.ShouldDoOverApproximateWeakClosure(
             static_cast<size_t>(idle_time_in_ms))))) {
     OverApproximateWeakClosure(
@@ skipping 101 matching lines @@
     case DO_SCAVENGE:
       CollectGarbage(NEW_SPACE, "idle notification: scavenge");
       break;
     case DO_FINALIZE_SWEEPING:
       mark_compact_collector()->EnsureSweepingCompleted();
       break;
     case DO_NOTHING:
       break;
   }
 
-  if (action.reduce_memory) {
-    new_space_.Shrink();
-    UncommitFromSpace();
-  }
+  ReduceNewSpaceSize(action);
   return result;
 }
 
 
 void Heap::IdleNotificationEpilogue(GCIdleTimeAction action,
                                     GCIdleTimeHandler::HeapState heap_state,
                                     double start_ms, double deadline_in_ms,
                                     bool is_long_idle_notification) {
   double idle_time_in_ms = deadline_in_ms - start_ms;
   double current_time = MonotonicallyIncreasingTimeInMs();
@@ skipping 1876 matching lines @@
     *object_type = "CODE_TYPE";                                                \
     *object_sub_type = "CODE_AGE/" #name;                                      \
     return true;
     CODE_AGE_LIST_COMPLETE(COMPARE_AND_RETURN_NAME)
 #undef COMPARE_AND_RETURN_NAME
   }
   return false;
 }
 }
 }  // namespace v8::internal