Simplified garbage collection idle handler.

src/heap/gc-idle-time-handler.cc

 // Copyright 2014 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/gc-idle-time-handler.h"
 #include "src/heap/gc-tracer.h"
 #include "src/utils.h"
 
 namespace v8 {
 namespace internal {
 
 const double GCIdleTimeHandler::kConservativeTimeRatio = 0.9;
 const size_t GCIdleTimeHandler::kMaxMarkCompactTimeInMs = 1000;
 const size_t GCIdleTimeHandler::kMaxFinalIncrementalMarkCompactTimeInMs = 1000;
 const size_t GCIdleTimeHandler::kMinTimeForFinalizeSweeping = 100;
-const int GCIdleTimeHandler::kMaxMarkCompactsInIdleRound = 7;
+const int GCIdleTimeHandler::kMaxMarkCompactsInIdleRound = 2;
 const int GCIdleTimeHandler::kIdleScavengeThreshold = 5;
 const double GCIdleTimeHandler::kHighContextDisposalRate = 100;
 const size_t GCIdleTimeHandler::kMinTimeForOverApproximatingWeakClosureInMs = 1;
 
 
 void GCIdleTimeAction::Print() {
   switch (type) {
     case DONE:
       PrintF("done");
       break;
@@ skipping 119 matching lines @@
       return true;
     }
   }
   return false;
 }
 
 
 bool GCIdleTimeHandler::ShouldDoMarkCompact(
     size_t idle_time_in_ms, size_t size_of_objects,
     size_t mark_compact_speed_in_bytes_per_ms) {
-  return idle_time_in_ms >=
-         EstimateMarkCompactTime(size_of_objects,
-                                 mark_compact_speed_in_bytes_per_ms);
+  return idle_time_in_ms >= kMaxScheduledIdleTime &&
+         idle_time_in_ms >=
+             EstimateMarkCompactTime(size_of_objects,
+                                     mark_compact_speed_in_bytes_per_ms);
 }
 
 
 bool GCIdleTimeHandler::ShouldDoContextDisposalMarkCompact(
     int contexts_disposed, double contexts_disposal_rate) {
   return contexts_disposed > 0 && contexts_disposal_rate > 0 &&
          contexts_disposal_rate < kHighContextDisposalRate;
 }
 
 
@@ skipping 60 matching lines @@
       StartIdleRound();
     } else {
       return GCIdleTimeAction::Done();
     }
   }
 
   if (heap_state.incremental_marking_stopped) {
     if (ShouldDoMarkCompact(static_cast<size_t>(idle_time_in_ms),
                             heap_state.size_of_objects,
                             heap_state.mark_compact_speed_in_bytes_per_ms)) {
-      // If there are no more than two GCs left in this idle round and we are
-      // allowed to do a full GC, then make those GCs full in order to compact
-      // the code space.
-      // TODO(ulan): Once we enable code compaction for incremental marking, we
-      // can get rid of this special case and always start incremental marking.
-      int remaining_mark_sweeps =
-          kMaxMarkCompactsInIdleRound - mark_compacts_since_idle_round_started_;
-      if (static_cast<size_t>(idle_time_in_ms) > kMaxScheduledIdleTime &&
-          (remaining_mark_sweeps <= 2 ||
-           !heap_state.can_start_incremental_marking)) {
-        return GCIdleTimeAction::FullGC();
-      }
-    }
-    if (!heap_state.can_start_incremental_marking) {
-      return GCIdleTimeAction::Nothing();
+      return GCIdleTimeAction::FullGC();
     }
   }
+
   // TODO(hpayer): Estimate finalize sweeping time.
   if (heap_state.sweeping_in_progress &&
       static_cast<size_t>(idle_time_in_ms) >= kMinTimeForFinalizeSweeping) {
     return GCIdleTimeAction::FinalizeSweeping();
   }
 
   if (heap_state.incremental_marking_stopped &&
       !heap_state.can_start_incremental_marking) {
     return GCIdleTimeAction::Nothing();
   }
   size_t step_size = EstimateMarkingStepSize(
       static_cast<size_t>(kIncrementalMarkingStepTimeInMs),
       heap_state.incremental_marking_speed_in_bytes_per_ms);
   return GCIdleTimeAction::IncrementalMarking(step_size);
 }
 }
 }