[heap] Use RAIL mode for starting incremental marking.

src/heap/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/heap/heap.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/ast/context-slot-cache.h"
 #include "src/base/bits.h"
@@ skipping 5290 matching lines @@
           "new limit: %" PRIuS " KB (%.1f)\n",
           old_gen_size / KB, old_generation_allocation_limit_ / KB, limit / KB,
           factor);
     }
     old_generation_allocation_limit_ = limit;
   }
 }
 
 bool Heap::ShouldOptimizeForLoadTime() {
   return isolate()->rail_mode() == PERFORMANCE_LOAD &&
-         PromotedTotalSize() < initial_old_generation_size_ &&
+         !AllocationLimitOvershotByLargeMargin() &&
          MonotonicallyIncreasingTimeInMs() <
              isolate()->LoadStartTimeMs() + kMaxLoadTimeMs;
 }
 
 // This predicate is called when an old generation space cannot allocated from
 // the free list and is about to add a new page. Returning false will cause a
 // major GC. It happens when the old generation allocation limit is reached and
 // - either we need to optimize for memory usage,
 // - or the incremental marking is not in progress and we cannot start it.
 bool Heap::ShouldExpandOldGenerationOnSlowAllocation() {
@@ skipping 31 matching lines @@
   if ((FLAG_stress_compaction && (gc_count_ & 1) != 0) ||
       HighMemoryPressure()) {
     // If there is high memory pressure or stress testing is enabled, then
     // start marking immediately.
     return IncrementalMarkingLimit::kHardLimit;
   }
   size_t old_generation_space_available = OldGenerationSpaceAvailable();
   if (old_generation_space_available > new_space_->Capacity()) {
     return IncrementalMarkingLimit::kNoLimit;
   }
-  // We are close to the allocation limit.
-  // Choose between the hard and the soft limits.
-  if (old_generation_space_available == 0 || ShouldOptimizeForMemoryUsage()) {
+  if (ShouldOptimizeForMemoryUsage()) {
+    return IncrementalMarkingLimit::kHardLimit;
+  }
+  if (ShouldOptimizeForLoadTime()) {
+    return IncrementalMarkingLimit::kNoLimit;
+  }
+  if (old_generation_space_available == 0) {
     return IncrementalMarkingLimit::kHardLimit;
   }
   return IncrementalMarkingLimit::kSoftLimit;
 }
 
 void Heap::EnableInlineAllocation() {
   if (!inline_allocation_disabled_) return;
   inline_allocation_disabled_ = false;
 
   // Update inline allocation limit for new space.
@@ skipping 1125 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8