Be more willing to expand old space when evacuating new space at the end of

src/spaces.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1602 matching lines @@
     }
     if (ratio <= ratio_threshold) return 0;  // Not fragmented.
 
     return static_cast<int>(ratio - ratio_threshold);
   }
 
   void EvictEvacuationCandidatesFromFreeLists();
 
   bool CanExpand();
 
+  // Expands the space by allocating a fixed number of pages. Returns false if
+  // it cannot allocate requested number of pages from OS, or if the hard heap
+  // size limit has been hit.
+  bool Expand();
+
   // Returns the number of total pages in this space.
   int CountTotalPages();
 
  protected:
   // Maximum capacity of this space.
   intptr_t max_capacity_;
 
   // Accounting information for this space.
   AllocationStats accounting_stats_;
 
   // The dummy page that anchors the double linked list of pages.
   Page anchor_;
 
   // The space's free list.
   FreeList free_list_;
 
   // Normal allocation information.
   AllocationInfo allocation_info_;
 
   // Bytes of each page that cannot be allocated.  Possibly non-zero
   // for pages in spaces with only fixed-size objects.  Always zero
   // for pages in spaces with variable sized objects (those pages are
   // padded with free-list nodes).
   int page_extra_;
 
   bool was_swept_conservatively_;
 
   Page* first_unswept_page_;
 
-  // Expands the space by allocating a fixed number of pages. Returns false if
-  // it cannot allocate requested number of pages from OS.
-  bool Expand();
-
   // Generic fast case allocation function that tries linear allocation at the
   // address denoted by top in allocation_info_.
   inline HeapObject* AllocateLinearly(int size_in_bytes);
 
   // Slow path of AllocateRaw.  This function is space-dependent.
   MUST_USE_RESULT virtual HeapObject* SlowAllocateRaw(int size_in_bytes);
 
   friend class PageIterator;
 };
 
@@ skipping 963 matching lines @@
   }
   // Must be small, since an iteration is used for lookup.
   static const int kMaxComments = 64;
 };
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_H_