Make the speed of incrmental marking depend also on the rate

src/spaces.cc

Index: src/spaces.cc
===================================================================
--- src/spaces.cc	(revision 12583)
+++ src/spaces.cc	(working copy)
@@ -447,6 +447,7 @@
   chunk->InitializeReservedMemory();
   chunk->slots_buffer_ = NULL;
   chunk->skip_list_ = NULL;
+  chunk->write_barrier_counter_ = kWriteBarrierCounterGranularity;
   chunk->ResetLiveBytes();
   Bitmap::Clear(chunk);
   chunk->initialize_scan_on_scavenge(false);
@@ -2042,7 +2043,7 @@
   // candidate.
   ASSERT(!MarkCompactCollector::IsOnEvacuationCandidate(new_node));
 
-  const int kThreshold = IncrementalMarking::kAllocatedThreshold;
+  const int kThreshold = IncrementalMarking::kIncrementalMarkingThreshold;
 
   // Memory in the linear allocation area is counted as allocated.  We may free
   // a little of this again immediately - see below.