An object should only be promoted to the old generation if it survived a scavenge operation.

src/mark-compact.cc

Index: src/mark-compact.cc
diff --git a/src/mark-compact.cc b/src/mark-compact.cc
index 61b1b54c7bd13c95acfe0b71f262e9dd6860c15f..2bdacaf78113366fcdaa24fefeedb7205eb3e4fe 100644
--- a/src/mark-compact.cc
+++ b/src/mark-compact.cc
@@ -2008,8 +2008,10 @@ int MarkCompactCollector::DiscoverAndPromoteBlackObjectsOnPage(
 
       offset++;
       current_cell >>= 1;
-      // Aggressively promote young survivors to the old space.
-      if (TryPromoteObject(object, size)) {
+
+      // TODO(hpayer): Refactor EvacuateObject and call this function instead.
+      if (heap_->ShouldBePromoted(object->address(), size) &&

[Michael Starzinger, 2014/06/18 10:46:39]

nit: s/heap_/heap()/

[Hannes Payer (out of office), 2014/06/18 11:40:29]

Done.

+          TryPromoteObject(object, size)) {
         continue;
       }