When allocation rate is low and we are close to the new space limit, we should perform a scavenge d…

test/unittests/heap/gc-idle-time-handler-unittest.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 <limits>
 
 #include "src/heap/gc-idle-time-handler.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace v8 {
@@ skipping 138 matching lines @@
   heap_state.used_new_space_size = kNewSpaceCapacity;
   heap_state.scavenge_speed_in_bytes_per_ms = 1 * KB;
   int idle_time_ms = 16;
   EXPECT_FALSE(GCIdleTimeHandler::ShouldDoScavenge(
       idle_time_ms, heap_state.new_space_capacity,
       heap_state.used_new_space_size, heap_state.scavenge_speed_in_bytes_per_ms,
       heap_state.new_space_allocation_throughput_in_bytes_per_ms));
 }
 
 
+TEST_F(GCIdleTimeHandlerTest, DoScavengeLowAllocationRate) {
+  GCIdleTimeHandler::HeapState heap_state = DefaultHeapState();
+  heap_state.used_new_space_size = kNewSpaceCapacity;
+  heap_state.new_space_allocation_throughput_in_bytes_per_ms =
+      GCIdleTimeHandler::kLowAllocationThroughput - 1;
+  int idle_time_ms = 16;
+  EXPECT_TRUE(GCIdleTimeHandler::ShouldDoScavenge(
+      idle_time_ms, heap_state.new_space_capacity,
+      heap_state.used_new_space_size, heap_state.scavenge_speed_in_bytes_per_ms,
+      heap_state.new_space_allocation_throughput_in_bytes_per_ms));
+}
+
+
 TEST_F(GCIdleTimeHandlerTest, DoScavengeHighScavengeSpeed) {
   GCIdleTimeHandler::HeapState heap_state = DefaultHeapState();
   heap_state.used_new_space_size = kNewSpaceCapacity;
   heap_state.scavenge_speed_in_bytes_per_ms = kNewSpaceCapacity;
   int idle_time_ms = 16;
   EXPECT_TRUE(GCIdleTimeHandler::ShouldDoScavenge(
       idle_time_ms, heap_state.new_space_capacity,
       heap_state.used_new_space_size, heap_state.scavenge_speed_in_bytes_per_ms,
       heap_state.new_space_allocation_throughput_in_bytes_per_ms));
 }
@@ skipping 249 matching lines @@
   // Simulate incremental marking stopped and not eligible to start.
   heap_state.incremental_marking_stopped = true;
   double idle_time_ms = 10.0;
   // We should return DONE if we cannot start incremental marking.
   GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
   EXPECT_EQ(DONE, action.type);
 }
 
 }  // namespace internal
 }  // namespace v8