Shrink the new space and uncommit marking deque on low memory notification.

test/cctest/test-heap.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 
 #include <stdlib.h>
 
 #include "v8.h"
 
 #include "execution.h"
 #include "factory.h"
 #include "macro-assembler.h"
 #include "global-handles.h"
@@ skipping 1204 matching lines @@
     intptr_t delta = size_of_objects_2 - size_of_objects_1;
     PrintF("Heap::SizeOfObjects: %" V8_PTR_PREFIX "d, "
            "Iterator: %" V8_PTR_PREFIX "d, "
            "delta: %" V8_PTR_PREFIX "d\n",
            size_of_objects_1, size_of_objects_2, delta);
     CHECK_GT(size_of_objects_2 / 20, delta);
   }
 }
 
 
+static void FillUpNewSpace(NewSpace* new_space) {
+  // Fill up new space to the point that it is completely full. Make sure
+  // that the scavenger does not undo the filling.
+  v8::HandleScope scope;
+  AlwaysAllocateScope always_allocate;
+  intptr_t available = new_space->EffectiveCapacity() - new_space->Size();
+  intptr_t number_of_fillers = (available / FixedArray::SizeFor(1000)) - 10;
+  for (intptr_t i = 0; i < number_of_fillers; i++) {
+    CHECK(HEAP->InNewSpace(*FACTORY->NewFixedArray(1000, NOT_TENURED)));
+  }
+}
+
+
 TEST(GrowAndShrinkNewSpace) {
   InitializeVM();
   NewSpace* new_space = HEAP->new_space();
 
   // Explicitly growing should double the space capacity.
   intptr_t old_capacity, new_capacity;
   old_capacity = new_space->Capacity();
   new_space->Grow();
   new_capacity = new_space->Capacity();
   CHECK(2 * old_capacity == new_capacity);
 
-  // Fill up new space to the point that it is completely full. Make sure
-  // that the scavenger does not undo the filling.
   old_capacity = new_space->Capacity();
-  {
-    v8::HandleScope scope;
-    AlwaysAllocateScope always_allocate;
-    intptr_t available = new_space->EffectiveCapacity() - new_space->Size();
-    intptr_t number_of_fillers = (available / FixedArray::SizeFor(1000)) - 10;
-    for (intptr_t i = 0; i < number_of_fillers; i++) {
-      CHECK(HEAP->InNewSpace(*FACTORY->NewFixedArray(1000, NOT_TENURED)));
-    }
-  }
+  FillUpNewSpace(new_space);
   new_capacity = new_space->Capacity();
   CHECK(old_capacity == new_capacity);
 
   // Explicitly shrinking should not affect space capacity.
   old_capacity = new_space->Capacity();
   new_space->Shrink();
   new_capacity = new_space->Capacity();
   CHECK(old_capacity == new_capacity);
 
   // Let the scavenger empty the new space.
   HEAP->CollectGarbage(NEW_SPACE);
   CHECK_LE(new_space->Size(), old_capacity);
 
   // Explicitly shrinking should halve the space capacity.
   old_capacity = new_space->Capacity();
   new_space->Shrink();
   new_capacity = new_space->Capacity();
   CHECK(old_capacity == 2 * new_capacity);
 
   // Consecutive shrinking should not affect space capacity.
   old_capacity = new_space->Capacity();
   new_space->Shrink();
   new_space->Shrink();
   new_space->Shrink();
   new_capacity = new_space->Capacity();
   CHECK(old_capacity == new_capacity);
 }
+
+
+TEST(CollectingAllAvailableGarbageShrinksNewSpace) {
+  InitializeVM();
+  v8::HandleScope scope;
+  NewSpace* new_space = HEAP->new_space();
+  intptr_t old_capacity, new_capacity;
+  old_capacity = new_space->Capacity();
+  new_space->Grow();
+  new_capacity = new_space->Capacity();
+  CHECK(2 * old_capacity == new_capacity);
+  FillUpNewSpace(new_space);
+  HEAP->CollectAllAvailableGarbage();
+  new_capacity = new_space->Capacity();
+  CHECK(old_capacity == new_capacity);
+}