diff --git a/script/mongodb.js b/script/mongodb.js
index 99e3f19..45470ed 100644
--- a/script/mongodb.js
+++ b/script/mongodb.js
@@ -58,7 +58,7 @@ db.proposal.createIndex({"proposal_id": 1}, {"unique": true});
 db.tx_msg.createIndex({"hash": 1}, {"unique": true});
 
 // init data
-db.sync_conf.insert({"block_num_per_worker_handle": 100, "max_worker_sleep_time": 120});
+db.sync_conf.insert({"block_num_per_worker_handle": 50, "max_worker_sleep_time": 120});
 
 // drop collection
 // db.account.drop();
diff --git a/service/task/task_execute.go b/service/task/task_execute.go
index a047a9a..0778fc5 100644
--- a/service/task/task_execute.go
+++ b/service/task/task_execute.go
@@ -23,7 +23,7 @@ func StartExecuteTask() {
 		blockNumPerWorkerHandle int64
 		maxWorkerSleepTime      int64
 	)
-	log := logger.GetLogger("StartCreateTask")
+	log := logger.GetLogger("TaskExecutor")
 
 	// get sync conf
 	syncConf, err := syncConfModel.GetConf()
@@ -56,13 +56,14 @@ func executeTask(blockNumPerWorkerHandle, maxWorkerSleepTime int64, chanLimit ch
 		workerId, taskType     string
 		blockChainLatestHeight int64
 	)
-	log := logger.GetLogger("StartCreateTask")
+	log := logger.GetLogger("TaskExecutor")
 	genWorkerId := func() string {
 		// generate worker id use hostname@xxx
 		hostname, _ := os.Hostname()
 		return fmt.Sprintf("%v@%v", hostname, bson.NewObjectId().Hex())
 	}
 
+	healthCheckQuit := make(chan bool)
 	workerId = genWorkerId()
 	client := helper.GetClient()
 
@@ -70,6 +71,7 @@ func executeTask(blockNumPerWorkerHandle, maxWorkerSleepTime int64, chanLimit ch
 		if r := recover(); r != nil {
 			log.Error("execute task fail", logger.Any("err", r))
 		}
+		close(healthCheckQuit)
 		<-chanLimit
 		client.Release()
 	}()
@@ -92,7 +94,6 @@ func executeTask(blockNumPerWorkerHandle, maxWorkerSleepTime int64, chanLimit ch
 	err = syncTaskModel.TakeOverTask(task, workerId)
 	if err != nil {
 		if err == mgo.ErrNotFound {
-			// this task has been take over by other goroutine
 			log.Info("Task has been take over by other goroutine")
 		} else {
 			log.Error("Take over task fail", logger.String("err", err.Error()))
@@ -109,7 +110,7 @@ func executeTask(blockNumPerWorkerHandle, maxWorkerSleepTime int64, chanLimit ch
 		taskType = document.SyncTaskTypeFollow
 	}
 	log.Info("worker begin execute task",
-		logger.String("cur_worker", workerId), logger.Any("task_id", task.ID),
+		logger.String("cur_worker", workerId), logger.String("task_id", task.ID.Hex()),
 		logger.String("from-to", fmt.Sprintf("%v-%v", task.StartHeight, task.EndHeight)))
 
 	// worker health check, if worker is alive, then update last update time every minute.
@@ -124,33 +125,43 @@ func executeTask(blockNumPerWorkerHandle, maxWorkerSleepTime int64, chanLimit ch
 		}()
 
 		for {
-			task, err := syncTaskModel.GetTaskByIdAndWorker(taskId, workerId)
-			if err == nil {
-				blockChainLatestHeight, err := getBlockChainLatestHeight()
+			select {
+			case <-healthCheckQuit:
+				logger.Info("get health check quit signal, now exit health check")
+				return
+			default:
+				task, err := syncTaskModel.GetTaskByIdAndWorker(taskId, workerId)
 				if err == nil {
-					if assertTaskValid(task, blockNumPerWorkerHandle, blockChainLatestHeight) {
-						// update task last update time
-						if err := syncTaskModel.UpdateLastUpdateTime(task); err != nil {
-							log.Error("update last update time fail", logger.String("err", err.Error()))
+					blockChainLatestHeight, err := getBlockChainLatestHeight()
+					if err == nil {
+						if assertTaskValid(task, blockNumPerWorkerHandle, blockChainLatestHeight) {
+							// update task last update time
+							if err := syncTaskModel.UpdateLastUpdateTime(task); err != nil {
+								log.Error("update last update time fail", logger.String("err", err.Error()),
+									logger.String("task_id", task.ID.Hex()))
+							}
+							logger.Info("health check success, now sleep one minute",
+								logger.String("task_id", task.ID.Hex()),
+								logger.String("task_current_worker", task.WorkerId))
+						} else {
+							log.Info("task is invalid, exit health check", logger.String("task_id", taskId.Hex()))
+							break
 						}
 					} else {
-						log.Info("task is invalid, exit health check", logger.String("task_id", taskId.Hex()))
-						break
+						log.Error("get block chain latest height fail", logger.String("err", err.Error()))
 					}
 				} else {
-					log.Error("get block chain latest height fail", logger.String("err", err.Error()))
-				}
-			} else {
-				if err == mgo.ErrNotFound {
-					log.Info("task may be task over by other goroutine, exit health check",
-						logger.String("task_id", taskId.Hex()), logger.String("current_worker", workerId))
-					break
-				} else {
-					log.Error("get task by id and worker fail", logger.String("task_id", taskId.Hex()),
-						logger.String("current_worker", workerId))
+					if err == mgo.ErrNotFound {
+						log.Info("task may be task over by other goroutine, exit health check",
+							logger.String("task_id", taskId.Hex()), logger.String("current_worker", workerId))
+						break
+					} else {
+						log.Error("get task by id and worker fail", logger.String("task_id", taskId.Hex()),
+							logger.String("current_worker", workerId))
+					}
 				}
+				time.Sleep(1 * time.Minute)
 			}
-			time.Sleep(1 * time.Minute)
 		}
 	}
 	go workerHealthCheck(task.ID, workerId)