Increase old generation space significantly if we observe a high promotion rate.

src/heap.h

 // Copyright 2012 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 1567 matching lines @@
   static const intptr_t kMinimumPromotionLimit = 5 * Page::kPageSize;
   static const intptr_t kMinimumAllocationLimit =
       8 * (Page::kPageSize > MB ? Page::kPageSize : MB);
 
   intptr_t OldGenPromotionLimit(intptr_t old_gen_size) {
     const int divisor = FLAG_stress_compaction ? 10 :
         new_space_high_promotion_mode_active_ ? 1 : 3;
     intptr_t limit =
         Max(old_gen_size + old_gen_size / divisor, kMinimumPromotionLimit);
     limit += new_space_.Capacity();
+    // TODO(hpayer): Can be removed when when pretenuring is supported for all
+    // allocation sites.
+    if (IsHighSurvivalRate() && IsStableOrIncreasingSurvivalTrend()) {
+      limit *= 2;
+    }
     intptr_t halfway_to_the_max = (old_gen_size + max_old_generation_size_) / 2;
     return Min(limit, halfway_to_the_max);
   }
 
   intptr_t OldGenAllocationLimit(intptr_t old_gen_size) {
     const int divisor = FLAG_stress_compaction ? 8 :
         new_space_high_promotion_mode_active_ ? 1 : 2;
     intptr_t limit =
         Max(old_gen_size + old_gen_size / divisor, kMinimumAllocationLimit);
     limit += new_space_.Capacity();
+    // TODO(hpayer): Can be removed when when pretenuring is supported for all
+    // allocation sites.
+    if (IsHighSurvivalRate() && IsStableOrIncreasingSurvivalTrend()) {
+      limit *= 2;
+    }
     intptr_t halfway_to_the_max = (old_gen_size + max_old_generation_size_) / 2;
     return Min(limit, halfway_to_the_max);
   }
 
   // Implements the corresponding V8 API function.
   bool IdleNotification(int hint);
 
   // Declare all the root indices.
   enum RootListIndex {
 #define ROOT_INDEX_DECLARATION(type, name, camel_name) k##camel_name##RootIndex,
@@ skipping 1489 matching lines @@
   AssertNoAllocation no_alloc;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_