Report DOM partitionAlloc size to V8 GC.

Source/core/dom/Node.cpp

Index: Source/core/dom/Node.cpp
diff --git a/Source/core/dom/Node.cpp b/Source/core/dom/Node.cpp
index 6490529549604567c25be4fcf3d918da4a3c43d2..eb113512c51b6a9f75dd571887ccaca9c0e6603b 100644
--- a/Source/core/dom/Node.cpp
+++ b/Source/core/dom/Node.cpp
@@ -106,12 +106,15 @@ using namespace HTMLNames;
 void* Node::operator new(size_t size)
 {
     ASSERT(isMainThread());
-    return partitionAlloc(Partitions::getObjectModelPartition(), size);
+    void* ptr = partitionAlloc(Partitions::getObjectModelPartition(), size);
+    Partitions::addDOMMemoryUsage(partitionAllocGetSize(ptr));

[haraken, 2014/05/28 07:11:34]

Won't this affect performance? I think this call path is very
performance-sensitive.

I think you can check performance using Dromaeo/dom-*.

[kouhei (in TOK), 2014/05/28 07:35:20]

Ack. Will test.

[esprehn, 2014/05/28 08:38:14]

Lots of nodes are not reachable or even reclaimable by v8.

[Hannes Payer (out of office), 2014/05/28 11:00:07]

Is this call here causing the reported performance degradation on Dromeo?

[eseidel, 2014/05/29 05:49:49]

Why would you want to report it during Node alloc?  Why not report it to v8
every time partitionAlloc allocs a new superpage or some other semi-infrequent
allocation from partitionAlloc directly?  Doesn't V8 want to know about memory
pressure from the entire renderer?

+    return ptr;
 }
 
 void Node::operator delete(void* ptr)
 {
     ASSERT(isMainThread());
+    Partitions::subtractDOMMemoryUsage(partitionAllocGetSize(ptr));
     partitionFree(ptr);
 }
 #endif