diff --git a/src/os/inc/os.h b/src/os/inc/os.h
index 6731ca6d7db9ce72e72a88a1b9dadf76fb8ec87e..903e80d5c7f554d420eafc9224fe5e7e35fe8467 100644
--- a/src/os/inc/os.h
+++ b/src/os/inc/os.h
@@ -29,7 +29,7 @@ extern "C" {
 #include "osMath.h"
 #include "osMemory.h"
 #include "osRand.h"
-#include "osSemphone.h"
+#include "osSemaphore.h"
 #include "osSignal.h"
 #include "osSleep.h"
 #include "osSocket.h"
diff --git a/src/os/inc/osSemphone.h b/src/os/inc/osSemaphore.h
similarity index 97%
rename from src/os/inc/osSemphone.h
rename to src/os/inc/osSemaphore.h
index fe59095205010bef553413809706c62cd772a7e3..10d14700e013f66e6d98208f0e65fe1ca5fc3874 100644
--- a/src/os/inc/osSemphone.h
+++ b/src/os/inc/osSemaphore.h
@@ -13,8 +13,8 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef TDENGINE_OS_SEMPHONE_H
-#define TDENGINE_OS_SEMPHONE_H
+#ifndef TDENGINE_OS_SEMAPHORE_H
+#define TDENGINE_OS_SEMAPHORE_H
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/src/os/src/darwin/dwSemphone.c b/src/os/src/darwin/dwSemaphore.c
similarity index 100%
rename from src/os/src/darwin/dwSemphone.c
rename to src/os/src/darwin/dwSemaphore.c
diff --git a/src/os/src/detail/osSemphone.c b/src/os/src/detail/osSemaphore.c
similarity index 100%
rename from src/os/src/detail/osSemphone.c
rename to src/os/src/detail/osSemaphore.c
diff --git a/src/os/src/windows/wSemphone.c b/src/os/src/windows/wSemaphore.c
similarity index 100%
rename from src/os/src/windows/wSemphone.c
rename to src/os/src/windows/wSemaphore.c
diff --git a/src/util/inc/tsched.h b/src/util/inc/tsched.h
index 3e481cbc327b495975fb03bc4e4d850e4372f044..a1591512c1f87f524837a7986e3c8b3e14e25924 100644
--- a/src/util/inc/tsched.h
+++ b/src/util/inc/tsched.h
@@ -28,10 +28,41 @@ typedef struct SSchedMsg {
   void *thandle;
 } SSchedMsg;
 
-void *taosInitScheduler(int queueSize, int numOfThreads, const char *label);
-void *taosInitSchedulerWithInfo(int queueSize, int numOfThreads, const char *label, void *tmrCtrl);
-int  taosScheduleTask(void *qhandle, SSchedMsg *pMsg);
-void taosCleanUpScheduler(void *param);
+/**
+ * Create a thread-safe ring-buffer based task queue and return the instance. A thread
+ * pool will be created to consume the messages in the queue.
+ * @param capacity the queue capacity
+ * @param numOfThreads the number of threads for the thread pool
+ * @param label the label of the queue
+ * @return the created queue scheduler
+ */
+void *taosInitScheduler(int capacity, int numOfThreads, const char *label);
+
+/**
+ * Create a thread-safe ring-buffer based task queue and return the instance.
+ * Same as taosInitScheduler, and it also print the queue status every 1 minite.
+ * @param capacity the queue capacity
+ * @param numOfThreads the number of threads for the thread pool
+ * @param label the label of the queue
+ * @param tmrCtrl the timer controller, tmr_ctrl_t*
+ * @return the created queue scheduler
+ */
+void *taosInitSchedulerWithInfo(int capacity, int numOfThreads, const char *label, void *tmrCtrl);
+
+/**
+ * Clean up the queue scheduler instance and free the memory.
+ * @param queueScheduler the queue scheduler to free
+ */
+void taosCleanUpScheduler(void *queueScheduler);
+
+/**
+ * Schedule a new task to run, the task is described by pMsg.
+ * The function may be blocked if no thread is available to execute the task.
+ * That may happen when all threads are busy.
+ * @param queueScheduler the queue scheduler instance
+ * @param pMsg the message for the task
+ */
+void taosScheduleTask(void *queueScheduler, SSchedMsg *pMsg);
 
 #ifdef __cplusplus
 }
diff --git a/src/util/src/tsched.c b/src/util/src/tsched.c
index f014dd0fab5494bd85f197e2c79fac53359e8edf..16142470c95678b8663f3bd437357dcdb22635a5 100644
--- a/src/util/src/tsched.c
+++ b/src/util/src/tsched.c
@@ -108,39 +108,47 @@ void *taosInitScheduler(int queueSize, int numOfThreads, const char *label) {
 
 void *taosInitSchedulerWithInfo(int queueSize, int numOfThreads, const char *label, void *tmrCtrl) {
   SSchedQueue* pSched = taosInitScheduler(queueSize, numOfThreads, label);
-  
+
   if (tmrCtrl != NULL && pSched != NULL) {
     pSched->pTmrCtrl = tmrCtrl;
     taosTmrReset(taosDumpSchedulerStatus, DUMP_SCHEDULER_TIME_WINDOW, pSched, pSched->pTmrCtrl, &pSched->pTimer);
   }
-  
+
   return pSched;
 }
 
-void *taosProcessSchedQueue(void *param) {
+void *taosProcessSchedQueue(void *scheduler) {
   SSchedMsg    msg;
-  SSchedQueue *pSched = (SSchedQueue *)param;
+  SSchedQueue *pSched = (SSchedQueue *)scheduler;
+  int ret = 0;
 
   while (1) {
-    if (tsem_wait(&pSched->fullSem) != 0) {
-      uError("wait %s fullSem failed(%s)", pSched->label, strerror(errno));
+    if ((ret = tsem_wait(&pSched->fullSem)) != 0) {
+      uFatal("wait %s fullSem failed(%s)", pSched->label, strerror(errno));
+      exit(ret);
     }
     if (pSched->stop) {
       break;
     }
 
-    if (pthread_mutex_lock(&pSched->queueMutex) != 0)
-      uError("lock %s queueMutex failed(%s)", pSched->label, strerror(errno));
+    if ((ret = pthread_mutex_lock(&pSched->queueMutex)) != 0) {
+      uFatal("lock %s queueMutex failed(%s)", pSched->label, strerror(errno));
+      exit(ret);
+    }
 
     msg = pSched->queue[pSched->fullSlot];
     memset(pSched->queue + pSched->fullSlot, 0, sizeof(SSchedMsg));
     pSched->fullSlot = (pSched->fullSlot + 1) % pSched->queueSize;
 
-    if (pthread_mutex_unlock(&pSched->queueMutex) != 0)
-      uError("unlock %s queueMutex failed(%s)", pSched->label, strerror(errno));
+    if ((ret = pthread_mutex_unlock(&pSched->queueMutex)) != 0) {
+      uFatal("unlock %s queueMutex failed(%s)", pSched->label, strerror(errno));
+      exit(ret);
+    }
 
-    if (tsem_post(&pSched->emptySem) != 0)
-      uError("post %s emptySem failed(%s)", pSched->label, strerror(errno));
+    if ((ret = tsem_post(&pSched->emptySem)) != 0) {
+      uFatal("post %s emptySem failed(%s)", pSched->label, strerror(errno));
+      exit(ret);
+    }
 
     if (msg.fp)
       (*(msg.fp))(&msg);
@@ -151,30 +159,37 @@ void *taosProcessSchedQueue(void *param) {
   return NULL;
 }
 
-int taosScheduleTask(void *qhandle, SSchedMsg *pMsg) {
-  SSchedQueue *pSched = (SSchedQueue *)qhandle;
+void taosScheduleTask(void *queueScheduler, SSchedMsg *pMsg) {
+  SSchedQueue *pSched = (SSchedQueue *)queueScheduler;
+  int ret = 0;
+
   if (pSched == NULL) {
     uError("sched is not ready, msg:%p is dropped", pMsg);
-    return 0;
+    return;
   }
 
-  if (tsem_wait(&pSched->emptySem) != 0) {
-    uError("wait %s emptySem failed(%s)", pSched->label, strerror(errno));
+  if ((ret = tsem_wait(&pSched->emptySem)) != 0) {
+    uFatal("wait %s emptySem failed(%s)", pSched->label, strerror(errno));
+    exit(ret);
   }
 
-  if (pthread_mutex_lock(&pSched->queueMutex) != 0)
-    uError("lock %s queueMutex failed(%s)", pSched->label, strerror(errno));
+  if ((ret = pthread_mutex_lock(&pSched->queueMutex)) != 0) {
+    uFatal("lock %s queueMutex failed(%s)", pSched->label, strerror(errno));
+    exit(ret);
+  }
 
   pSched->queue[pSched->emptySlot] = *pMsg;
   pSched->emptySlot = (pSched->emptySlot + 1) % pSched->queueSize;
 
-  if (pthread_mutex_unlock(&pSched->queueMutex) != 0)
-    uError("unlock %s queueMutex failed(%s)", pSched->label, strerror(errno));
-
-  if (tsem_post(&pSched->fullSem) != 0) 
-    uError("post %s fullSem failed(%s)", pSched->label, strerror(errno));
+  if ((ret = pthread_mutex_unlock(&pSched->queueMutex)) != 0) {
+    uFatal("unlock %s queueMutex failed(%s)", pSched->label, strerror(errno));
+    exit(ret);
+  }
 
-  return 0;
+  if ((ret = tsem_post(&pSched->fullSem)) != 0) {
+    uFatal("post %s fullSem failed(%s)", pSched->label, strerror(errno));
+    exit(ret);
+  }
 }
 
 void taosCleanUpScheduler(void *param) {
@@ -219,4 +234,4 @@ void taosDumpSchedulerStatus(void *qhandle, void *tmrId) {
   }
   
   taosTmrReset(taosDumpSchedulerStatus, DUMP_SCHEDULER_TIME_WINDOW, pSched, pSched->pTmrCtrl, &pSched->pTimer);
-}
+}
\ No newline at end of file