diff --git a/cyber/BUILD b/cyber/BUILD
index 5f3b237c31b353819fcdc3cf27952c30a7d0c89d..1333c47e510ce832297797c13ad7f54ed9395258 100644
--- a/cyber/BUILD
+++ b/cyber/BUILD
@@ -61,6 +61,7 @@ cc_library(
         "//cyber:state",
         "//cyber/logger:async_logger",
         "//cyber/node",
+        "//cyber/timer:timing_wheel",
     ],
 )
 
diff --git a/cyber/init.cc b/cyber/init.cc
index ff6d94f79144dba7e6a49d309bfb72657153273b..d4e4e09d550c8d0b9fca03f0c4cbd4dc23bc9035 100644
--- a/cyber/init.cc
+++ b/cyber/init.cc
@@ -31,7 +31,7 @@
 #include "cyber/scheduler/scheduler.h"
 #include "cyber/service_discovery/topology_manager.h"
 #include "cyber/task/task.h"
-#include "cyber/timer/timer_manager.h"
+#include "cyber/timer/timing_wheel.h"
 #include "cyber/transport/transport.h"
 
 namespace apollo {
@@ -114,7 +114,7 @@ void Clear() {
     return;
   }
   TaskManager::CleanUp();
-  TimerManager::CleanUp();
+  TimingWheel::CleanUp();
   scheduler::CleanUp();
   service_discovery::TopologyManager::CleanUp();
   transport::Transport::CleanUp();
diff --git a/cyber/timer/BUILD b/cyber/timer/BUILD
index 2975f44eeba4b8fdac16780c9dcfadd2ef44a5fd..d3f8ea9ed1017456e61cb12ed104b92776b05540 100644
--- a/cyber/timer/BUILD
+++ b/cyber/timer/BUILD
@@ -6,53 +6,22 @@ cc_library(
     name = "timer",
     srcs = ["timer.cc"],
     hdrs = ["timer.h"],
-    deps = [
-        "timer_manager",
-        "//cyber/common:global_data",
-    ],
-)
-
-cc_library(
-    name = "timer_manager",
-    srcs = ["timer_manager.cc"],
-    hdrs = ["timer_manager.h"],
     deps = [
         "timing_wheel",
-        "//cyber/common:macros",
-        "//cyber/scheduler",
-        "//cyber/task",
-        "//cyber/time",
-        "//cyber/time:rate",
-    ],
-)
-
-cc_test(
-    name = "timer_manager_test",
-    size = "small",
-    srcs = ["timer_manager_test.cc"],
-    deps = [
-        "//cyber:cyber_core",
-        "@gtest//:main",
+        "//cyber/common:global_data",
     ],
 )
 
 cc_library(
     name = "timer_task",
-    srcs = ["timer_task.cc"],
     hdrs = ["timer_task.h"],
-    deps = [
-        "//cyber/base:bounded_queue",
-        "//cyber/task",
-    ],
 )
 
 cc_library(
-    name = "timing_slot",
-    srcs = ["timing_slot.cc"],
-    hdrs = ["timing_slot.h"],
+    name = "timer_bucket",
+    hdrs = ["timer_bucket.h"],
     deps = [
         "timer_task",
-        "//cyber/base:bounded_queue",
     ],
 )
 
@@ -61,19 +30,18 @@ cc_library(
     srcs = ["timing_wheel.cc"],
     hdrs = ["timing_wheel.h"],
     deps = [
-        "timer_task",
-        "timing_slot",
-        "//cyber/base:bounded_queue",
+        "timer_bucket",
         "//cyber/task",
         "//cyber/time",
         "//cyber/time:duration",
+        "//cyber/time:rate",
     ],
 )
 
 cc_test(
-    name = "timing_wheel_test",
+    name = "timer_test",
     size = "small",
-    srcs = ["timing_wheel_test.cc"],
+    srcs = ["timer_test.cc"],
     deps = [
         "//cyber:cyber_core",
         "//cyber:init",
diff --git a/cyber/timer/timer.cc b/cyber/timer/timer.cc
index aba520747f82142d6e7964907428f4ea28680656..1e6b688967e89e7c3894e1d6c9ce256ee23c05e8 100644
--- a/cyber/timer/timer.cc
+++ b/cyber/timer/timer.cc
@@ -1,5 +1,5 @@
 /******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
+ * Copyright 2019 The Apollo Authors. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,14 +21,24 @@
 namespace apollo {
 namespace cyber {
 
-Timer::Timer() { tm_ = TimerManager::Instance(); }
+namespace {
+static std::atomic<uint64_t> global_timer_id = {0};
+static uint64_t GenerateTimerId() { return global_timer_id.fetch_add(1); }
+}
+
+Timer::Timer() {
+  timing_wheel_ = TimingWheel::Instance();
+  timer_id_ = GenerateTimerId();
+}
 
 Timer::Timer(TimerOption opt) : timer_opt_(opt) {
-  tm_ = TimerManager::Instance();
+  timing_wheel_ = TimingWheel::Instance();
+  timer_id_ = GenerateTimerId();
 }
 
 Timer::Timer(uint32_t period, std::function<void()> callback, bool oneshot) {
-  tm_ = TimerManager::Instance();
+  timing_wheel_ = TimingWheel::Instance();
+  timer_id_ = GenerateTimerId();
   timer_opt_.period = period;
   timer_opt_.callback = callback;
   timer_opt_.oneshot = oneshot;
@@ -36,28 +46,68 @@ Timer::Timer(uint32_t period, std::function<void()> callback, bool oneshot) {
 
 void Timer::SetTimerOption(TimerOption opt) { timer_opt_ = opt; }
 
+bool Timer::InitTimerTask() {
+  if (timer_opt_.period == 0) {
+    AERROR << "Max interval must great than 0";
+    return false;
+  }
+
+  if (timer_opt_.period >= TIMER_MAX_INTERVAL_MS) {
+    AERROR << "Max interval must less than " << TIMER_MAX_INTERVAL_MS;
+    return false;
+  }
+
+  task_.reset(new TimerTask(timer_id_));
+  task_->interval_ms = timer_opt_.period;
+  task_->next_fire_duration_ms = task_->interval_ms;
+
+  if (timer_opt_.oneshot) {
+    task_->callback = timer_opt_.callback;
+  } else {
+    std::weak_ptr<TimerTask> task_wptr = this->task_;
+    task_->callback = [this, task_wptr]() {
+      auto start = std::chrono::steady_clock::now();
+      this->timer_opt_.callback();
+      auto end = std::chrono::steady_clock::now();
+      uint64_t execute_time_ms =
+          std::chrono::duration_cast<std::chrono::milliseconds>(end - start)
+              .count();
+      auto task = task_wptr.lock();
+      if (task) {
+        if (execute_time_ms >= task->interval_ms) {
+          task->next_fire_duration_ms = 1;
+        } else {
+          task->next_fire_duration_ms = task->interval_ms - execute_time_ms;
+        }
+        this->timing_wheel_->AddTask(task);
+      }
+    };
+  }
+  return true;
+}
+
 void Timer::Start() {
   if (!common::GlobalData::Instance()->IsRealityMode()) {
     return;
   }
 
   if (!started_.exchange(true)) {
-    timer_id_ =
-        tm_->Add(timer_opt_.period, timer_opt_.callback, timer_opt_.oneshot);
+    if (InitTimerTask()) {
+      timing_wheel_->AddTask(task_);
+    }
   }
 }
 
 void Timer::Stop() {
   if (started_.exchange(false)) {
-    ADEBUG << "stop timer " << timer_id_;
-    tm_->Remove(timer_id_);
-    timer_id_ = 0;
+    ADEBUG << "stop timer ";
+    task_.reset();
   }
 }
 
 Timer::~Timer() {
-  if (timer_id_ != 0) {
-    tm_->Remove(timer_id_);
+  if (task_) {
+    Stop();
   }
 }
 
diff --git a/cyber/timer/timer.h b/cyber/timer/timer.h
index d50193d849ea69e12f159162389305a28f8529a3..7ade4fed84fa9cf89edeea73520b60d3b4dba351 100644
--- a/cyber/timer/timer.h
+++ b/cyber/timer/timer.h
@@ -1,5 +1,5 @@
 /******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
+ * Copyright 2019 The Apollo Authors. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,13 +20,16 @@
 #include <atomic>
 #include <memory>
 
-#include "cyber/timer/timer_manager.h"
+#include "cyber/timer/timing_wheel.h"
 
 namespace apollo {
 namespace cyber {
 
 struct TimerOption {
-  uint32_t period;                 // The period of the timer, unit is ms
+  TimerOption(uint32_t period, std::function<void()> callback, bool oneshot)
+      : period(period), callback(callback), oneshot(oneshot) {}
+  TimerOption() : period(0), callback(), oneshot() {}
+  uint32_t period = 0;             // The period of the timer, unit is ms
   std::function<void()> callback;  // The tasks that the timer needs to perform
   bool oneshot;  // True: perform the callback only after the first timing cycle
                  // False: perform the callback every timed period
@@ -74,9 +77,11 @@ class Timer {
   void Stop();
 
  private:
+  bool InitTimerTask();
+  uint64_t timer_id_;
   TimerOption timer_opt_;
-  TimerManager* tm_ = nullptr;
-  uint64_t timer_id_ = 0;
+  TimingWheel* timing_wheel_ = nullptr;
+  std::shared_ptr<TimerTask> task_;
   std::atomic<bool> started_ = {false};
 };
 
diff --git a/cyber/timer/timer_task.cc b/cyber/timer/timer_bucket.h
similarity index 58%
rename from cyber/timer/timer_task.cc
rename to cyber/timer/timer_bucket.h
index 5918e5f7015adbafff6ea629fed1b2159f680357..cca2c450e64c9d5cb5ffb21d5059a161a89b9258 100644
--- a/cyber/timer/timer_task.cc
+++ b/cyber/timer/timer_bucket.h
@@ -1,5 +1,5 @@
 /******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
+ * Copyright 2019 The Apollo Authors. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -14,32 +14,34 @@
  * limitations under the License.
  *****************************************************************************/
 
-#include "cyber/timer/timer_task.h"
+#ifndef CYBER_TIMER_TIMER_BUCKET_H_
+#define CYBER_TIMER_TIMER_BUCKET_H_
+
+#include <list>
+#include <memory>
+#include <mutex>
 
-#include "cyber/task/task.h"
+#include "cyber/timer/timer_task.h"
 
 namespace apollo {
 namespace cyber {
 
-void TimerTask::Fire(bool async) {
-  if (status_ != INIT) {
-    return;
-  }
-  if (oneshot_)  // not repeat. so always on ready
-    status_ = EXPIRED;
-  if (async) {
-    cyber::Async(handler_);
-  } else {
-    handler_();
+class TimerBucket {
+ public:
+  void AddTask(const std::shared_ptr<TimerTask>& task) {
+    std::lock_guard<std::mutex> lock(mutex_);
+    task_list_.push_back(task);
   }
-}
 
-bool TimerTask::Cancel() {
-  if (State() != INIT) {
-    return false;
-  }
-  status_ = CANCELED;
-  return true;
-}
+  std::mutex& mutex() { return mutex_; }
+  std::list<std::weak_ptr<TimerTask>>& task_list() { return task_list_; }
+
+ private:
+  std::mutex mutex_;
+  std::list<std::weak_ptr<TimerTask>> task_list_;
+};
+
 }  // namespace cyber
 }  // namespace apollo
+
+#endif  // CYBER_TIMER_TIMER_BUCKET_H_
diff --git a/cyber/timer/timer_manager.cc b/cyber/timer/timer_manager.cc
deleted file mode 100644
index 0c561a298adc0d0ef0f9f5e56520424e646ac5e1..0000000000000000000000000000000000000000
--- a/cyber/timer/timer_manager.cc
+++ /dev/null
@@ -1,82 +0,0 @@
-/******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *****************************************************************************/
-
-#include "cyber/timer/timer_manager.h"
-
-#include "cyber/common/log.h"
-#include "cyber/scheduler/scheduler_factory.h"
-#include "cyber/time/duration.h"
-#include "cyber/time/rate.h"
-
-namespace apollo {
-namespace cyber {
-
-TimerManager::TimerManager()
-    : timing_wheel_(Duration(0.01)),
-      time_gran_(Duration(0.01)),
-      running_(false) {}  // default time gran = 1ms
-
-TimerManager::~TimerManager() {
-  if (running_) {
-    Shutdown();
-  }
-}
-
-void TimerManager::Start() {
-  std::lock_guard<std::mutex> lock(running_mutex_);
-  if (!running_) {
-    ADEBUG << "TimerManager->Start() ok";
-    running_ = true;
-    scheduler_thread_ = std::thread([this]() { this->ThreadFuncImpl(); });
-    scheduler::Instance()->SetInnerThreadAttr("timer", &scheduler_thread_);
-  }
-}
-
-void TimerManager::Shutdown() {
-  std::lock_guard<std::mutex> lock(running_mutex_);
-  if (running_) {
-    running_ = false;
-    if (scheduler_thread_.joinable()) {
-      scheduler_thread_.join();
-    }
-  }
-}
-
-uint64_t TimerManager::Add(uint64_t interval, std::function<void()> handler,
-                           bool oneshot) {
-  if (!running_) {
-    Start();
-  }
-  uint64_t timer_id = timing_wheel_.StartTimer(interval, handler, oneshot);
-  return timer_id;
-}
-
-void TimerManager::Remove(uint64_t timer_id) {
-  timing_wheel_.StopTimer(timer_id);
-}
-
-bool TimerManager::IsRunning() { return running_; }
-
-void TimerManager::ThreadFuncImpl() {
-  Rate rate(time_gran_);
-  while (running_) {
-    timing_wheel_.Step();
-    rate.Sleep();
-  }
-}
-
-}  // namespace cyber
-}  // namespace apollo
diff --git a/cyber/timer/timer_manager.h b/cyber/timer/timer_manager.h
deleted file mode 100644
index 98ceed74b15d6b06ec07acc5d854c0c08d12814a..0000000000000000000000000000000000000000
--- a/cyber/timer/timer_manager.h
+++ /dev/null
@@ -1,58 +0,0 @@
-/******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *****************************************************************************/
-
-#ifndef CYBER_TIMER_TIMER_MANAGER_H_
-#define CYBER_TIMER_TIMER_MANAGER_H_
-
-#include <fstream>
-#include <iostream>
-#include <list>
-#include <memory>
-#include <mutex>
-#include <string>
-#include <thread>
-
-#include "cyber/common/macros.h"
-#include "cyber/time/duration.h"
-#include "cyber/timer/timing_wheel.h"
-
-namespace apollo {
-namespace cyber {
-
-class TimerManager {
- public:
-  virtual ~TimerManager();
-  void Start();
-  void Shutdown();
-  bool IsRunning();
-  uint64_t Add(uint64_t interval, std::function<void()> handler, bool oneshot);
-  void Remove(uint64_t timer_id);
-
- private:
-  TimingWheel timing_wheel_;
-  Duration time_gran_;
-  bool running_ = false;
-  mutable std::mutex running_mutex_;
-  std::thread scheduler_thread_;
-  void ThreadFuncImpl();
-
-  DECLARE_SINGLETON(TimerManager)
-};
-
-}  // namespace cyber
-}  // namespace apollo
-
-#endif  // CYBER_TIMER_TIMER_MANAGER_H_
diff --git a/cyber/timer/timer_manager_test.cc b/cyber/timer/timer_manager_test.cc
deleted file mode 100644
index efcd77994234f1d947f61556ddba4f6735680370..0000000000000000000000000000000000000000
--- a/cyber/timer/timer_manager_test.cc
+++ /dev/null
@@ -1,37 +0,0 @@
-/******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *****************************************************************************/
-
-#include "cyber/timer/timer_manager.h"
-
-#include <gtest/gtest.h>
-#include <memory>
-
-#include "cyber/common/log.h"
-
-namespace apollo {
-namespace cyber {
-
-TEST(TimerManagerTest, Basic) {
-  auto tm = TimerManager::Instance();
-  ASSERT_EQ(tm->IsRunning(), false);
-  tm->Start();
-  ASSERT_EQ(tm->IsRunning(), true);
-  tm->Shutdown();
-  ASSERT_EQ(tm->IsRunning(), false);
-}
-
-}  // namespace cyber
-}  // namespace apollo
diff --git a/cyber/timer/timer_task.h b/cyber/timer/timer_task.h
index f12d648a75a1920eeaadc267195a08245c977647..596a25a487a162d70b7f020c86883b864a2aafd0 100644
--- a/cyber/timer/timer_task.h
+++ b/cyber/timer/timer_task.h
@@ -1,5 +1,5 @@
 /******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
+ * Copyright 2019 The Apollo Authors. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,55 +17,20 @@
 #ifndef CYBER_TIMER_TIMER_TASK_H_
 #define CYBER_TIMER_TIMER_TASK_H_
 
-#include <algorithm>
-#include <iostream>
-#include <list>
-#include <map>
-#include <memory>
-#include <mutex>
-#include <thread>
-#include <unordered_map>
-#include <utility>
-#include <vector>
-
-#include "cyber/base/bounded_queue.h"
+#include <functional>
 
 namespace apollo {
 namespace cyber {
 
-using CallHandler = std::function<void()>;
-
-class TimerTask {
- public:
-  TimerTask(uint64_t id, uint64_t it, uint64_t ivl, CallHandler h, bool ons)
-      : tid_(id), init_time_(it), interval_(ivl), handler_(h), oneshot_(ons) {}
-  TimerTask() = default;
-
- private:
-  enum STATS { INIT = 0, CANCELED, EXPIRED };
-  STATS State() { return status_; }
-  volatile STATS status_ = INIT;
-  uint64_t tid_ = 0;
-
- public:
-  uint64_t init_time_ = 0;
-  uint64_t deadline_ = 0;
-  uint64_t interval_ = 0;
-  CallHandler handler_;
-  uint64_t rest_rounds_ = 0;
-  bool oneshot_ = true;
-  uint64_t fire_count_ = 0;
-
- public:
-  uint64_t Id() { return tid_; }
-
-  void Fire(bool async);
-
-  bool Cancel();
-
-  bool IsCanceled() { return State() == CANCELED; }
+class TimerBucket;
 
-  bool IsExpired() { return State() == EXPIRED; }
+struct TimerTask {
+  explicit TimerTask(uint64_t timer_id) : timer_id_(timer_id) {}
+  uint64_t timer_id_ = 0;
+  std::function<void()> callback;
+  uint64_t interval_ms = 0;
+  uint64_t remainder_interval_ms = 0;
+  uint64_t next_fire_duration_ms = 0;
 };
 
 }  // namespace cyber
diff --git a/cyber/timer/timer_test.cc b/cyber/timer/timer_test.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e370b8a20bc9fa7ab668049cae1f34f50ce2d305
--- /dev/null
+++ b/cyber/timer/timer_test.cc
@@ -0,0 +1,103 @@
+/******************************************************************************
+ * Copyright 2018 The Apollo Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *****************************************************************************/
+
+/* note that the frame code of the following is Generated by script  */
+
+#include <gtest/gtest.h>
+#include <iostream>
+#include <memory>
+#include <string>
+#include <utility>
+
+#include "cyber/common/util.h"
+#include "cyber/cyber.h"
+#include "cyber/init.h"
+
+#include "cyber/timer/timer.h"
+
+namespace apollo {
+namespace cyber {
+namespace timer {
+
+using cyber::Timer;
+using cyber::TimerOption;
+
+TEST(TimerTest, one_shot) {
+  int count = 0;
+  Timer timer(100, [&count] { count = 100; }, true);
+  timer.Start();
+  std::this_thread::sleep_for(std::chrono::milliseconds(90));
+  EXPECT_EQ(0, count);
+  std::this_thread::sleep_for(std::chrono::milliseconds(100));
+  EXPECT_EQ(100, count);
+  timer.Stop();
+}
+
+TEST(TimerTest, cycle) {
+  int count = 0;
+  Timer timers[1000];
+  TimerOption opt;
+  opt.oneshot = false;
+  opt.callback = [=] { AINFO << count; };
+  for (int i = 0; i < 1000; i++) {
+    opt.period = i + 1;
+    timers[i].SetTimerOption(opt);
+    timers[i].Start();
+  }
+
+  std::this_thread::sleep_for(std::chrono::seconds(3));
+  for (int i = 0; i < 1000; i++) {
+    timers[i].Stop();
+  }
+}
+
+TEST(TimerTest, start_stop) {
+  int count = 0;
+  Timer timer(2, [count] { AINFO << count; }, false);
+  for (int i = 0; i < 100; i++) {
+    timer.Start();
+    std::this_thread::sleep_for(std::chrono::milliseconds(10));
+    timer.Stop();
+  }
+}
+
+TEST(TimerTest, test1) {
+  auto count = 0;
+
+  auto func = [count]() { AINFO << count; };
+
+  TimerOption to{1000, func, false};
+
+  {
+    Timer t;
+    t.SetTimerOption(to);
+    common::GlobalData::Instance()->EnableSimulationMode();
+    t.Start();
+    common::GlobalData::Instance()->DisableSimulationMode();
+    t.Start();
+    t.Start();
+  }
+}
+
+}  // namespace timer
+}  // namespace cyber
+}  // namespace apollo
+
+int main(int argc, char** argv) {
+  testing::InitGoogleTest(&argc, argv);
+  apollo::cyber::Init(argv[0]);
+  return RUN_ALL_TESTS();
+}
diff --git a/cyber/timer/timing_slot.cc b/cyber/timer/timing_slot.cc
deleted file mode 100644
index e57aa0e286fb2fcbd65385e55e4350441a7d0249..0000000000000000000000000000000000000000
--- a/cyber/timer/timing_slot.cc
+++ /dev/null
@@ -1,65 +0,0 @@
-/******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *****************************************************************************/
-
-#include "cyber/timer/timing_slot.h"
-
-#include "cyber/common/log.h"
-#include "cyber/timer/timer_task.h"
-
-namespace apollo {
-namespace cyber {
-
-void TimingSlot::AddTask(const std::shared_ptr<TimerTask>& task) {
-  tasks_.emplace(task->Id(), task);
-}
-
-void TimingSlot::EnumTaskList(
-    uint64_t deadline, bool async, BoundedQueue<HandlePackage>* hander_queue,
-    BoundedQueue<std::shared_ptr<TimerTask>>* rep_queue) {
-  for (auto it = tasks_.begin(); it != tasks_.end();) {
-    auto task = it->second;  // *it;
-    auto del_it = it;
-    it++;
-    // std::cout << "judge: task->" << task->deadline << " : " << deadline;
-    if (task->deadline_ <= deadline) {
-      if (task->rest_rounds_ == 0) {
-        if (async) {
-          HandlePackage hp;
-          hp.handle = task->handler_;
-          hp.id = task->Id();
-          if (!hander_queue->Enqueue(hp)) {
-            AERROR << "hander queue is full";
-          }
-        } else {
-          task->Fire(false);
-        }
-
-        if (!task->oneshot_) {  // repeat timer,push back
-          task->fire_count_++;
-          rep_queue->Enqueue(task);
-        }
-        tasks_.erase(del_it);
-
-      } else {
-        AERROR << "task deadline overflow...";
-      }
-    } else {  // no expired, -- rounds
-      task->rest_rounds_--;
-    }
-  }
-}
-}  // namespace cyber
-}  // namespace apollo
diff --git a/cyber/timer/timing_slot.h b/cyber/timer/timing_slot.h
deleted file mode 100644
index d3c99fdc5ba88ed35eb93a57796ce5558f490ed0..0000000000000000000000000000000000000000
--- a/cyber/timer/timing_slot.h
+++ /dev/null
@@ -1,64 +0,0 @@
-/******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *****************************************************************************/
-
-#ifndef CYBER_TIMER_TIMING_SLOT_H_
-#define CYBER_TIMER_TIMING_SLOT_H_
-
-#include <algorithm>
-#include <iostream>
-#include <list>
-#include <map>
-#include <memory>
-#include <mutex>
-#include <thread>
-#include <unordered_map>
-#include <utility>
-#include <vector>
-
-#include "cyber/base/bounded_queue.h"
-
-namespace apollo {
-namespace cyber {
-
-using apollo::cyber::base::BoundedQueue;
-using CallHandler = std::function<void()>;
-
-class TimerTask;
-
-struct HandlePackage {
-  uint64_t id;
-  CallHandler handle;
-};
-
-class TimingSlot {
- private:
-  //  no needs for multi-thread
-  std::unordered_map<uint64_t, std::shared_ptr<TimerTask>> tasks_;
-
- public:
-  TimingSlot() = default;
-  void AddTask(const std::shared_ptr<TimerTask>& task);
-  void RemoveTask(uint64_t id) { tasks_.erase(id); }
-
-  void EnumTaskList(uint64_t deadline, bool async,
-                    BoundedQueue<HandlePackage>* hander_queue,
-                    BoundedQueue<std::shared_ptr<TimerTask>>* rep_list);
-};  // TimeSlot end
-
-}  // namespace cyber
-}  // namespace apollo
-
-#endif  // CYBER_TIMER_TIMING_SLOT_H_
diff --git a/cyber/timer/timing_wheel.cc b/cyber/timer/timing_wheel.cc
index aff2372732f88c1691893e6da66cae96e854d0a9..22d1039c8bce43af04ab1ab6fef8d93de40462cd 100644
--- a/cyber/timer/timing_wheel.cc
+++ b/cyber/timer/timing_wheel.cc
@@ -1,5 +1,5 @@
 /******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
+ * Copyright 2019 The Apollo Authors. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,164 +15,109 @@
  *****************************************************************************/
 
 #include "cyber/timer/timing_wheel.h"
-
-#include <algorithm>
-
-#include "cyber/base/for_each.h"
-#include "cyber/common/log.h"
 #include "cyber/task/task.h"
-#include "cyber/time/time.h"
-#include "cyber/timer/timer_task.h"
 
 namespace apollo {
 namespace cyber {
 
-TimingWheel::TimingWheel() {
-  if (!add_queue_.Init(BOUNDED_QUEUE_SIZE)) {
-    AERROR << "Add queue init failed.";
-    throw std::runtime_error("Add queue init failed.");
-  }
-  if (!repeat_queue_.Init(BOUNDED_QUEUE_SIZE)) {
-    AERROR << "Repeated task queue init failed.";
-    throw std::runtime_error("Repeated queue init failed.");
-  }
-  if (!handler_queue_.Init(BOUNDED_QUEUE_SIZE)) {
-    AERROR << "Handler queue init failed.";
-    throw std::runtime_error("Handler queue init failed.");
-  }
-}
-
-TimingWheel::TimingWheel(const Duration& tick_duration) {
-  tick_duration_ = tick_duration.ToNanosecond();
-  resolution_ = tick_duration_ / 1000000UL;
-  if (!add_queue_.Init(BOUNDED_QUEUE_SIZE)) {
-    AERROR << "Add queue init failed.";
-    throw std::runtime_error("Add queue init failed.");
-  }
-  if (!repeat_queue_.Init(BOUNDED_QUEUE_SIZE)) {
-    AERROR << "Repeated task queue init failed.";
-    throw std::runtime_error("Repeated queue init failed.");
-  }
-  if (!handler_queue_.Init(BOUNDED_QUEUE_SIZE)) {
-    AERROR << "Handler queue init failed.";
-    throw std::runtime_error("Handler queue init failed.");
-  }
-}
-
-uint64_t TimingWheel::StartTimer(uint64_t interval, CallHandler handler,
-                                 bool oneshot) {
-  if (id_counter_ > UINT64_MAX) {
-    AERROR << "Timer ID pool is full.";
-    return -1;
-  } else if (interval > TIMER_TASK_MAX_INTERVAL) {
-    AERROR << "The interval of timer task MUST less than or equal "
-           << TIMER_TASK_MAX_INTERVAL << "ms.";
-    return -1;
-  } else if (interval < resolution_) {
-    AERROR << "The interval of timer task MUST larger than or equal "
-           << resolution_ << "ms.";
-    return -1;
-  }
-  auto now = Time::Now().ToNanosecond();
-  auto task = std::make_shared<TimerTask>(
-      ++id_counter_, now, interval,
-      [handler](void) {
-        static std::mutex task_mutex;
-        std::lock_guard<std::mutex> lock(task_mutex);
-        handler();
-      },
-      oneshot);
-  if (add_queue_.Enqueue(task)) {
-    ADEBUG << "start timer id: " << id_counter_;
-    return id_counter_;
-  } else {
-    --id_counter_;
-    AERROR << "add queue is full, Enqueue failed!";
-    return -1;
+void TimingWheel::Start() {
+  std::lock_guard<std::mutex> lock(running_mutex_);
+  if (!running_) {
+    ADEBUG << "TimeWheel start ok";
+    running_ = true;
+    tick_thread_ = std::thread([this]() { this->TickFunc(); });
+    scheduler::Instance()->SetInnerThreadAttr("timer", &tick_thread_);
   }
 }
 
-void TimingWheel::Step() {
-  if (start_time_ == 0) {
-    start_time_ = Time::Now().ToNanosecond();
-  }
-  uint64_t deadline = tick_duration_ * (tick_ + 1);
-  uint64_t idx = tick_ & mask_;
-  RemoveCancelledTasks(idx);
-  FillAddSlot();
-  time_slots_[idx].EnumTaskList(deadline, true, &handler_queue_,
-                                &repeat_queue_);
-
-  // timing wheel tick one time
-  tick_++;
-
-  FillRepeatSlot();
-
-  while (!handler_queue_.Empty()) {
-    HandlePackage hp;
-    if (handler_queue_.Dequeue(&hp)) {
-      cyber::Async(hp.handle);
+void TimingWheel::Shutdown() {
+  std::lock_guard<std::mutex> lock(running_mutex_);
+  if (running_) {
+    running_ = false;
+    if (tick_thread_.joinable()) {
+      tick_thread_.join();
     }
   }
 }
 
-void TimingWheel::StopTimer(uint64_t timer_id) {
+void TimingWheel::Tick() {
+  auto& bucket = work_wheel_[current_work_wheel_index_];
   {
-    std::lock_guard<std::mutex> lg(cancelled_mutex_);
-    cancelled_list_.push_back(timer_id);
+    std::lock_guard<std::mutex> lock(bucket.mutex());
+    auto ite = bucket.task_list().begin();
+    while (ite != bucket.task_list().end()) {
+      auto task = ite->lock();
+      if (task) {
+        ADEBUG << "index: " << current_work_wheel_index_
+               << " timer id: " << task->timer_id_;
+        auto callback = task->callback;
+        cyber::Async([this, callback] {
+          if (this->running_) {
+            callback();
+          }
+        });
+      }
+      ite = bucket.task_list().erase(ite);
+    }
+  }
+  current_work_wheel_index_ = GetWorkWheelIndex(current_work_wheel_index_ + 1);
+  if (current_work_wheel_index_ == 0) {
+    current_assistant_wheel_index_ =
+        GetAssistantWheelIndex(current_assistant_wheel_index_ + 1);
+    Cascade(current_assistant_wheel_index_);
   }
 }
 
-void TimingWheel::RemoveCancelledTasks(uint64_t slot_index) {
-  if (slot_index >= TIMING_WHEEL_SIZE) {
-    return;
-  }
-  {
-    std::lock_guard<std::mutex> lg(cancelled_mutex_);
-    for (auto id : cancelled_list_) {
-      FOR_EACH(i, 0, TIMING_WHEEL_SIZE) { time_slots_[i].RemoveTask(id); }
+void TimingWheel::AddTask(const std::shared_ptr<TimerTask>& task) {
+  if (!running_) {
+    Start();
+  }
+
+  auto work_wheel_index =
+      current_work_wheel_index_ + task->next_fire_duration_ms;
+  if (work_wheel_index >= WORK_WHEEL_SIZE) {
+    auto real_work_wheel_index = GetWorkWheelIndex(work_wheel_index);
+    task->remainder_interval_ms = real_work_wheel_index;
+    auto assistant_ticks = work_wheel_index / WORK_WHEEL_SIZE;
+    if (assistant_ticks == 1 &&
+        real_work_wheel_index != current_work_wheel_index_) {
+      work_wheel_[real_work_wheel_index].AddTask(task);
+      ADEBUG << "add task to work wheel. index :" << real_work_wheel_index;
+    } else {
+      auto assistant_wheel_index = GetAssistantWheelIndex(
+          current_assistant_wheel_index_ + assistant_ticks);
+      assistant_wheel_[assistant_wheel_index].AddTask(task);
+      ADEBUG << "add task to assistant wheel. index : "
+             << assistant_wheel_index;
     }
-    cancelled_list_.clear();
+  } else {
+    work_wheel_[work_wheel_index].AddTask(task);
+    ADEBUG << "add task to work wheel. index :" << work_wheel_index;
   }
 }
 
-void TimingWheel::FillAddSlot() {
-  std::shared_ptr<TimerTask> task;
-  while (!add_queue_.Empty()) {
-    if (!add_queue_.Dequeue(&task)) {
-      return;
+void TimingWheel::Cascade(const uint64_t assistant_wheel_index) {
+  auto& bucket = assistant_wheel_[assistant_wheel_index];
+  std::lock_guard<std::mutex> lock(bucket.mutex());
+  auto ite = bucket.task_list().begin();
+  while (ite != bucket.task_list().end()) {
+    auto task = ite->lock();
+    if (task) {
+      work_wheel_[task->remainder_interval_ms].AddTask(task);
     }
-    FillSlot(task);
+    ite = bucket.task_list().erase(ite);
   }
 }
 
-void TimingWheel::FillRepeatSlot() {
-  std::shared_ptr<TimerTask> task;
-  while (!repeat_queue_.Empty()) {
-    if (!repeat_queue_.Dequeue(&task)) {
-      return;
-    }
-    FillSlot(task);
+void TimingWheel::TickFunc() {
+  Rate rate(TIMER_RESOLUTION_MS * 1000000);  // ms to ns
+  while (running_) {
+    Tick();
+    rate.Sleep();
   }
 }
 
-void TimingWheel::FillSlot(const std::shared_ptr<TimerTask>& task) {
-  task->deadline_ = task->init_time_ +
-                    (task->fire_count_ + 1) * (task->interval_) * 1000 * 1000 -
-                    start_time_;
+TimingWheel::TimingWheel() {}
 
-  // Calculate how many tickes have been run since the time wheel start
-  uint64_t t = task->deadline_ / tick_duration_;  // perTick = 1ms
-  if (t < tick_) {
-    task->rest_rounds_ = 0;
-  } else {
-    task->rest_rounds_ = (t - tick_) / TIMING_WHEEL_SIZE;
-  }
-  uint64_t ticks = std::max(t, tick_);  // right now
-  uint64_t idx = ticks & mask_;
-  time_slots_[idx].AddTask(task);
-
-  ADEBUG << "task id " << task->Id() << " insert to index " << idx;
-}
 }  // namespace cyber
 }  // namespace apollo
diff --git a/cyber/timer/timing_wheel.h b/cyber/timer/timing_wheel.h
index d7b172b489f2215fa03c42395d38a5e6d8c84836..c6fc694ce96b19d45149a37b868e1633ce3c1c5e 100644
--- a/cyber/timer/timing_wheel.h
+++ b/cyber/timer/timing_wheel.h
@@ -1,5 +1,5 @@
 /******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
+ * Copyright 2019 The Apollo Authors. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,74 +17,65 @@
 #ifndef CYBER_TIMER_TIMING_WHEEL_H_
 #define CYBER_TIMER_TIMING_WHEEL_H_
 
-#include <algorithm>
-#include <functional>
-#include <iostream>
+#include <future>
 #include <list>
-#include <map>
 #include <memory>
-#include <mutex>
 #include <thread>
-#include <unordered_map>
-#include <utility>
-#include <vector>
 
-#include "cyber/base/bounded_queue.h"
-#include "cyber/time/duration.h"
-#include "cyber/timer/timing_slot.h"
+#include "cyber/common/log.h"
+#include "cyber/common/macros.h"
+#include "cyber/scheduler/scheduler_factory.h"
+#include "cyber/time/rate.h"
+#include "cyber/timer/timer_bucket.h"
 
 namespace apollo {
 namespace cyber {
 
-using apollo::cyber::base::BoundedQueue;
-using CallHandler = std::function<void()>;
+struct TimerTask;
 
-static const int TIMING_WHEEL_SIZE = 128;
-static const int THREAD_POOL_SIZE = 4;
-static const uint64_t BOUNDED_QUEUE_SIZE = 200;
-static const int TIMER_TASK_MAX_INTERVAL = 1000;
-
-class TimerTask;
+static const uint64_t WORK_WHEEL_SIZE = 512;
+static const uint64_t ASSISTANT_WHEEL_SIZE = 64;
+static const uint64_t TIMER_RESOLUTION_MS = 1;
+static const uint64_t TIMER_MAX_INTERVAL_MS =
+    WORK_WHEEL_SIZE * ASSISTANT_WHEEL_SIZE;
 
 class TimingWheel {
  public:
-  TimingWheel();
-  explicit TimingWheel(const Duration& tick_duration);
-  ~TimingWheel() = default;
-
-  uint64_t StartTimer(uint64_t interval, CallHandler handler, bool oneshot);
-
-  void StopTimer(uint64_t timer_id);
-
-  void Step();
+  ~TimingWheel() {
+    if (running_) {
+      Shutdown();
+    }
+  }
 
- private:
-  void FillAddSlot();
-  void FillRepeatSlot();
-  void FillSlot(const std::shared_ptr<TimerTask>& task);
-
-  void RemoveCancelledTasks(uint64_t slot_index);
+  void Start();
 
-  uint64_t id_counter_ = 0;
+  void Shutdown();
 
-  uint64_t tick_ = 0;
+  void Tick();
 
-  uint64_t start_time_ = 0;
+  void AddTask(const std::shared_ptr<TimerTask>& task);
 
-  TimingSlot time_slots_[TIMING_WHEEL_SIZE];
+  void Cascade(const uint64_t assistant_wheel_index);
 
-  uint64_t mask_ = TIMING_WHEEL_SIZE - 1;
+  void TickFunc();
 
-  uint64_t tick_duration_ = 10 * 1000 * 1000;  // 10ms
-  uint64_t resolution_ = 10;                   // 10ms
-
-  // we need implement a lock-free high performance concurrent queue.
-  // Now, just a blocking-queue just for works.
-  std::list<uint64_t> cancelled_list_;
-  std::mutex cancelled_mutex_;
-  BoundedQueue<std::shared_ptr<TimerTask>> add_queue_;
-  BoundedQueue<std::shared_ptr<TimerTask>> repeat_queue_;
-  BoundedQueue<HandlePackage> handler_queue_;
+ private:
+  uint64_t GetWorkWheelIndex(const uint64_t index) {
+    return index & (WORK_WHEEL_SIZE - 1);
+  }
+  uint64_t GetAssistantWheelIndex(const uint64_t index) {
+    return index & (ASSISTANT_WHEEL_SIZE - 1);
+  }
+
+  bool running_ = false;
+  std::mutex running_mutex_;
+  TimerBucket work_wheel_[WORK_WHEEL_SIZE];
+  TimerBucket assistant_wheel_[ASSISTANT_WHEEL_SIZE];
+  uint64_t current_work_wheel_index_ = 0;
+  uint64_t current_assistant_wheel_index_ = 0;
+  std::thread tick_thread_;
+
+  DECLARE_SINGLETON(TimingWheel)
 };
 
 }  // namespace cyber
diff --git a/cyber/timer/timing_wheel_test.cc b/cyber/timer/timing_wheel_test.cc
deleted file mode 100644
index b6a09a707816484a40de9ead9372792a0c0c928f..0000000000000000000000000000000000000000
--- a/cyber/timer/timing_wheel_test.cc
+++ /dev/null
@@ -1,82 +0,0 @@
-/******************************************************************************
- * Copyright 2018 The Apollo Authors. All Rights Reserved.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *****************************************************************************/
-
-#include "cyber/timer/timing_wheel.h"
-
-#include <gtest/gtest.h>
-#include <unistd.h>
-#include <atomic>
-#include <memory>
-
-#include "cyber/common/log.h"
-#include "cyber/cyber.h"
-#include "cyber/init.h"
-
-namespace apollo {
-namespace cyber {
-
-class TestHandler {
- public:
-  TestHandler() = default;
-
-  void increment() { count_++; }
-
-  uint64_t count() { return count_; }
-
- private:
-  std::atomic<uint64_t> count_ = {0};
-};
-
-TEST(TimingWheelTest, Oneshot) {
-  TimingWheel tw;
-  std::shared_ptr<TestHandler> th(new TestHandler());
-  ASSERT_EQ(0, th->count());
-  std::function<void(void)> f = std::bind(&TestHandler::increment, th.get());
-  tw.Step();
-  tw.StartTimer(10, f, true);
-  for (int i = 0; i < 10; i++) {
-    tw.Step();
-    usleep(1000);
-  }
-  ASSERT_EQ(1, th->count());
-}
-
-TEST(TimingWheelTest, Period) {
-  TimingWheel tw;
-  std::shared_ptr<TestHandler> th(new TestHandler());
-  ASSERT_EQ(0, th->count());
-  std::function<void(void)> f = std::bind(&TestHandler::increment, th.get());
-  tw.Step();
-  tw.StartTimer(10, f, false);
-
-  for (uint64_t i = 0; i < 100; i++) {
-    tw.Step();
-    if ((i + 1) % 10 == 0) {
-      usleep(10 * 1000);
-      ASSERT_TRUE(i <= th->count() && i + 1 >= th->count());
-    }
-  }
-}
-
-}  // namespace cyber
-}  // namespace apollo
-
-int main(int argc, char** argv) {
-  testing::InitGoogleTest(&argc, argv);
-  apollo::cyber::Init(argv[0]);
-  auto res = RUN_ALL_TESTS();
-  return res;
-}
diff --git a/cyber/transport/BUILD b/cyber/transport/BUILD
index 187e17b12213789934cee747e5398d6e1c615945..9da466a4ad3d45524ad34507d3099cde7a601b9c 100644
--- a/cyber/transport/BUILD
+++ b/cyber/transport/BUILD
@@ -30,7 +30,7 @@ cc_library(
         "underlay_message",
         "underlay_message_type",
         "//cyber/service_discovery:role",
-        "//cyber/timer:timer_manager",
+        "//cyber/task:task",
         "@fastrtps",
     ],
 )