Change TaskQueueImpl to use a Deque with an inline capacity of 8

third_party/WebKit/Source/platform/scheduler/base/task_queue_impl.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_BASE_TASK_QUEUE_IMPL_H_
 #define THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_BASE_TASK_QUEUE_IMPL_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 302 matching lines @@
   // Push the task onto the |immediate_incoming_queue| and for auto pumped
   // queues it calls MaybePostDoWorkOnMainRunner if the Incoming queue was
   // empty.
   void PushOntoImmediateIncomingQueueLocked(
       const tracked_objects::Location& posted_from,
       base::OnceClosure task,
       base::TimeTicks desired_run_time,
       EnqueueOrder sequence_number,
       bool nestable);
 
+  // We reserve an inline capacity of 8 tasks to try and reduce the load on
+  // PartitionAlloc.
+  using TaskDeque = WTF::Deque<Task, 8>;
+
   // Extracts all the tasks from the immediate incoming queue and clears it.
   // Can be called from any thread.
-  WTF::Deque<TaskQueueImpl::Task> TakeImmediateIncomingQueue();
+  TaskDeque TakeImmediateIncomingQueue();
 
   void TraceQueueSize() const;
-  static void QueueAsValueInto(const WTF::Deque<Task>& queue,
+  static void QueueAsValueInto(const TaskDeque& queue,
                                base::TimeTicks now,
                                base::trace_event::TracedValue* state);
   static void QueueAsValueInto(const std::priority_queue<Task>& queue,
                                base::TimeTicks now,
                                base::trace_event::TracedValue* state);
   static void TaskAsValueInto(const Task& task,
                               base::TimeTicks now,
                               base::trace_event::TracedValue* state);
 
   void RemoveQueueEnabledVoter(const QueueEnabledVoterImpl* voter);
@@ skipping 26 matching lines @@
   MainThreadOnly& main_thread_only() {
     DCHECK(main_thread_checker_.CalledOnValidThread());
     return main_thread_only_;
   }
   const MainThreadOnly& main_thread_only() const {
     DCHECK(main_thread_checker_.CalledOnValidThread());
     return main_thread_only_;
   }
 
   mutable base::Lock immediate_incoming_queue_lock_;
-  WTF::Deque<Task> immediate_incoming_queue_;
-  WTF::Deque<Task>& immediate_incoming_queue() {
+  TaskDeque immediate_incoming_queue_;
+  TaskDeque& immediate_incoming_queue() {
     immediate_incoming_queue_lock_.AssertAcquired();
     return immediate_incoming_queue_;
   }
-  const WTF::Deque<Task>& immediate_incoming_queue() const {
+  const TaskDeque& immediate_incoming_queue() const {
     immediate_incoming_queue_lock_.AssertAcquired();
     return immediate_incoming_queue_;
   }
 
   const bool should_monitor_quiescence_;
   const bool should_notify_observers_;
   const bool should_report_when_execution_blocked_;
 
   DISALLOW_COPY_AND_ASSIGN(TaskQueueImpl);
 };
 
 }  // namespace internal
 }  // namespace scheduler
 }  // namespace blink
 
 #endif  // THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_BASE_TASK_QUEUE_IMPL_H_