diff --git a/source/libs/sync/inc/syncRespMgr.h b/source/libs/sync/inc/syncRespMgr.h
index 22e1005e5c495c6f4f17c452418d8b028d0cfffa..9026ecb66efc02f4e0e01d392063c1bdf4a5bdcb 100644
--- a/source/libs/sync/inc/syncRespMgr.h
+++ b/source/libs/sync/inc/syncRespMgr.h
@@ -41,13 +41,12 @@ typedef struct SSyncRespMgr {
 
 SSyncRespMgr *syncRespMgrCreate(void *data, int64_t ttl);
 void          syncRespMgrDestroy(SSyncRespMgr *pObj);
-int64_t       syncRespMgrAdd(SSyncRespMgr *pObj, SRespStub *pStub);
-int32_t       syncRespMgrDel(SSyncRespMgr *pObj, uint64_t index);
-int32_t       syncRespMgrGet(SSyncRespMgr *pObj, uint64_t index, SRespStub *pStub);
-int32_t       syncRespMgrGetAndDel(SSyncRespMgr *pObj, uint64_t index, SRespStub *pStub);
+uint64_t      syncRespMgrAdd(SSyncRespMgr *pObj, const SRespStub *pStub);
+int32_t       syncRespMgrDel(SSyncRespMgr *pObj, uint64_t seq);
+int32_t       syncRespMgrGet(SSyncRespMgr *pObj, uint64_t seq, SRespStub *pStub);
+int32_t       syncRespMgrGetAndDel(SSyncRespMgr *pObj, uint64_t seq, SRpcHandleInfo *pInfo);
 void          syncRespClean(SSyncRespMgr *pObj);
 void          syncRespCleanRsp(SSyncRespMgr *pObj);
-void          syncRespCleanByTTL(SSyncRespMgr *pObj, int64_t ttl, bool rsp);
 
 #ifdef __cplusplus
 }
diff --git a/source/libs/sync/inc/syncTools.h b/source/libs/sync/inc/syncTools.h
index 932432d1f89a78a2e86cc63b7c1ad94dc807f6a1..193579030f2c65b89bb74d21a4b9e87f38beb9dc 100644
--- a/source/libs/sync/inc/syncTools.h
+++ b/source/libs/sync/inc/syncTools.h
@@ -26,9 +26,6 @@ typedef struct SRaftId {
   SyncGroupId vgId;
 } SRaftId;
 
-// for compatibility, the same as syncPropose
-int32_t syncForwardToPeer(int64_t rid, SRpcMsg* pMsg, bool isWeak);
-
 // ------------------ for debug -------------------
 void syncRpcMsgPrint(SRpcMsg* pMsg);
 void syncRpcMsgPrint2(char* s, SRpcMsg* pMsg);
diff --git a/source/libs/sync/src/syncMain.c b/source/libs/sync/src/syncMain.c
index 19015c00b9fae1e2c1adff68b54c80f5b65ad1f8..14823be0982be118d51163d52e5ec961fcdb7733 100644
--- a/source/libs/sync/src/syncMain.c
+++ b/source/libs/sync/src/syncMain.c
@@ -452,11 +452,6 @@ int32_t syncNodeLeaderTransferTo(SSyncNode* pSyncNode, SNodeInfo newLeader) {
   return ret;
 }
 
-int32_t syncForwardToPeer(int64_t rid, SRpcMsg* pMsg, bool isWeak) {
-  int32_t ret = syncPropose(rid, pMsg, isWeak);
-  return ret;
-}
-
 SSyncState syncGetState(int64_t rid) {
   SSyncState state = {.state = TAOS_SYNC_STATE_ERROR};
 
@@ -558,109 +553,27 @@ SyncIndex syncNodeGetSnapshotConfigIndex(SSyncNode* pSyncNode, SyncIndex snapsho
   return lastIndex;
 }
 
-#if 0
-SyncTerm syncGetMyTerm(int64_t rid) {
-  SSyncNode* pSyncNode = syncNodeAcquire(rid);
-  if (pSyncNode == NULL) {
-    return TAOS_SYNC_STATE_ERROR;
-  }
-  ASSERT(rid == pSyncNode->rid);
-  SyncTerm term = pSyncNode->pRaftStore->currentTerm;
-
-  syncNodeRelease(pSyncNode);
-  return term;
-}
-
-SyncIndex syncGetLastIndex(int64_t rid) {
-  SSyncNode* pSyncNode = syncNodeAcquire(rid);
-  if (pSyncNode == NULL) {
-    return SYNC_INDEX_INVALID;
-  }
-  ASSERT(rid == pSyncNode->rid);
-  SyncIndex lastIndex = syncNodeGetLastIndex(pSyncNode);
-
-  syncNodeRelease(pSyncNode);
-  return lastIndex;
-}
-
-SyncIndex syncGetCommitIndex(int64_t rid) {
-  SSyncNode* pSyncNode = syncNodeAcquire(rid);
-  if (pSyncNode == NULL) {
-    return SYNC_INDEX_INVALID;
-  }
-  ASSERT(rid == pSyncNode->rid);
-  SyncIndex cmtIndex = pSyncNode->commitIndex;
-
-  syncNodeRelease(pSyncNode);
-  return cmtIndex;
-}
-
-SyncGroupId syncGetVgId(int64_t rid) {
-  SSyncNode* pSyncNode = syncNodeAcquire(rid);
-  if (pSyncNode == NULL) {
-    return TAOS_SYNC_STATE_ERROR;
-  }
-  ASSERT(rid == pSyncNode->rid);
-  SyncGroupId vgId = pSyncNode->vgId;
-
-  syncNodeRelease(pSyncNode);
-  return vgId;
-}
-
-void syncGetEpSet(int64_t rid, SEpSet* pEpSet) {
-  SSyncNode* pSyncNode = syncNodeAcquire(rid);
-  if (pSyncNode == NULL) {
-    memset(pEpSet, 0, sizeof(*pEpSet));
-    return;
-  }
-  ASSERT(rid == pSyncNode->rid);
+void syncGetRetryEpSet(int64_t rid, SEpSet* pEpSet) {
   pEpSet->numOfEps = 0;
-  for (int32_t i = 0; i < pSyncNode->pRaftCfg->cfg.replicaNum; ++i) {
-    snprintf(pEpSet->eps[i].fqdn, sizeof(pEpSet->eps[i].fqdn), "%s", (pSyncNode->pRaftCfg->cfg.nodeInfo)[i].nodeFqdn);
-    pEpSet->eps[i].port = (pSyncNode->pRaftCfg->cfg.nodeInfo)[i].nodePort;
-    (pEpSet->numOfEps)++;
-    sInfo("vgId:%d, sync get epset: index:%d %s:%d", pSyncNode->vgId, i, pEpSet->eps[i].fqdn, pEpSet->eps[i].port);
-  }
-  pEpSet->inUse = pSyncNode->pRaftCfg->cfg.myIndex;
-  sInfo("vgId:%d, sync get epset in-use:%d", pSyncNode->vgId, pEpSet->inUse);
 
-  syncNodeRelease(pSyncNode);
-}
-#endif
-
-void syncGetRetryEpSet(int64_t rid, SEpSet* pEpSet) {
   SSyncNode* pSyncNode = syncNodeAcquire(rid);
-  if (pSyncNode == NULL) {
-    memset(pEpSet, 0, sizeof(*pEpSet));
-    return;
-  }
+  if (pSyncNode == NULL) return;
 
-  pEpSet->numOfEps = 0;
   for (int32_t i = 0; i < pSyncNode->pRaftCfg->cfg.replicaNum; ++i) {
-    snprintf(pEpSet->eps[i].fqdn, sizeof(pEpSet->eps[i].fqdn), "%s", (pSyncNode->pRaftCfg->cfg.nodeInfo)[i].nodeFqdn);
-    pEpSet->eps[i].port = (pSyncNode->pRaftCfg->cfg.nodeInfo)[i].nodePort;
-    (pEpSet->numOfEps)++;
-    sInfo("vgId:%d, sync get retry epset: index:%d %s:%d", pSyncNode->vgId, i, pEpSet->eps[i].fqdn,
-          pEpSet->eps[i].port);
+    SEp* pEp = &pEpSet->eps[i];
+    tstrncpy(pEp->fqdn, pSyncNode->pRaftCfg->cfg.nodeInfo[i].nodeFqdn, TSDB_FQDN_LEN);
+    pEp->port = (pSyncNode->pRaftCfg->cfg.nodeInfo)[i].nodePort;
+    pEpSet->numOfEps++;
+    sInfo("vgId:%d, sync get retry epset, index:%d %s:%d", pSyncNode->vgId, i, pEp->fqdn, pEp->port);
   }
   if (pEpSet->numOfEps > 0) {
     pEpSet->inUse = (pSyncNode->pRaftCfg->cfg.myIndex + 1) % pEpSet->numOfEps;
   }
-  sInfo("vgId:%d, sync get retry epset in-use:%d", pSyncNode->vgId, pEpSet->inUse);
 
+  sInfo("vgId:%d, sync get retry epset numOfEps:%d inUse:%d", pSyncNode->vgId, pEpSet->numOfEps, pEpSet->inUse);
   syncNodeRelease(pSyncNode);
 }
 
-static void syncGetAndDelRespRpc(SSyncNode* pSyncNode, uint64_t index, SRpcHandleInfo* pInfo) {
-  SRespStub stub;
-  int32_t   ret = syncRespMgrGetAndDel(pSyncNode->pSyncRespMgr, index, &stub);
-  if (ret == 1) {
-    *pInfo = stub.rpcMsg.info;
-  }
-
-  sTrace("vgId:%d, get seq:%" PRIu64 " rpc handle:%p", pSyncNode->vgId, index, pInfo->handle);
-}
-
 int32_t syncPropose(int64_t rid, SRpcMsg* pMsg, bool isWeak) {
   SSyncNode* pSyncNode = syncNodeAcquire(rid);
   if (pSyncNode == NULL) {
@@ -2759,7 +2672,7 @@ int32_t syncNodeDoCommit(SSyncNode* ths, SyncIndex beginIndex, SyncIndex endInde
                 .flag = flag,
             };
 
-            syncGetAndDelRespRpc(ths, cbMeta.seqNum, &rpcMsg.info);
+            syncRespMgrGetAndDel(ths->pSyncRespMgr, cbMeta.seqNum, &rpcMsg.info);
             ths->pFsm->FpCommitCb(ths->pFsm, &rpcMsg, &cbMeta);
           }
         }
diff --git a/source/libs/sync/src/syncRespMgr.c b/source/libs/sync/src/syncRespMgr.c
index 56d5e944b85e33c43667a73740ec924f816bc23d..de8f1927ae4d4d1afe0ce7b744f35796d315157a 100644
--- a/source/libs/sync/src/syncRespMgr.c
+++ b/source/libs/sync/src/syncRespMgr.c
@@ -13,21 +13,22 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
+#define _DEFAULT_SOURCE
 #include "syncRespMgr.h"
 #include "syncRaftEntry.h"
 #include "syncRaftStore.h"
 
 SSyncRespMgr *syncRespMgrCreate(void *data, int64_t ttl) {
-  SSyncRespMgr *pObj = (SSyncRespMgr *)taosMemoryMalloc(sizeof(SSyncRespMgr));
+  SSyncRespMgr *pObj = taosMemoryCalloc(1, sizeof(SSyncRespMgr));
   if (pObj == NULL) {
     terrno = TSDB_CODE_OUT_OF_MEMORY;
     return NULL;
   }
-  memset(pObj, 0, sizeof(SSyncRespMgr));
 
   pObj->pRespHash =
       taosHashInit(sizeof(uint64_t), taosGetDefaultHashFunction(TSDB_DATA_TYPE_BINARY), true, HASH_NO_LOCK);
-  ASSERT(pObj->pRespHash != NULL);
+  if (pObj->pRespHash == NULL) return NULL;
+
   pObj->ttl = ttl;
   pObj->data = data;
   pObj->seqNum = 0;
@@ -38,93 +39,84 @@ SSyncRespMgr *syncRespMgrCreate(void *data, int64_t ttl) {
 
 void syncRespMgrDestroy(SSyncRespMgr *pObj) {
   if (pObj != NULL) {
-    taosThreadMutexLock(&(pObj->mutex));
+    taosThreadMutexLock(&pObj->mutex);
     taosHashCleanup(pObj->pRespHash);
-    taosThreadMutexUnlock(&(pObj->mutex));
+    taosThreadMutexUnlock(&pObj->mutex);
     taosThreadMutexDestroy(&(pObj->mutex));
     taosMemoryFree(pObj);
   }
 }
 
-int64_t syncRespMgrAdd(SSyncRespMgr *pObj, SRespStub *pStub) {
-  taosThreadMutexLock(&(pObj->mutex));
+uint64_t syncRespMgrAdd(SSyncRespMgr *pObj, const SRespStub *pStub) {
+  taosThreadMutexLock(&pObj->mutex);
 
-  uint64_t keyCode = ++(pObj->seqNum);
-  taosHashPut(pObj->pRespHash, &keyCode, sizeof(keyCode), pStub, sizeof(SRespStub));
+  uint64_t seq = ++(pObj->seqNum);
+  int32_t  code = taosHashPut(pObj->pRespHash, &seq, sizeof(uint64_t), pStub, sizeof(SRespStub));
+  sNTrace(pObj->data, "save message handle:%p, type:%s seq:%" PRIu64 " code:0x%x", pStub->rpcMsg.info.handle,
+          TMSG_INFO(pStub->rpcMsg.msgType), seq, code);
 
-  sNTrace(pObj->data, "save message handle, type:%s seq:%" PRIu64 " handle:%p", TMSG_INFO(pStub->rpcMsg.msgType),
-          keyCode, pStub->rpcMsg.info.handle);
-  taosThreadMutexUnlock(&(pObj->mutex));
-  return keyCode;
+  taosThreadMutexUnlock(&pObj->mutex);
+  return seq;
 }
 
-int32_t syncRespMgrDel(SSyncRespMgr *pObj, uint64_t index) {
-  taosThreadMutexLock(&(pObj->mutex));
+int32_t syncRespMgrDel(SSyncRespMgr *pObj, uint64_t seq) {
+  taosThreadMutexLock(&pObj->mutex);
 
-  taosHashRemove(pObj->pRespHash, &index, sizeof(index));
+  int32_t code = taosHashRemove(pObj->pRespHash, &seq, sizeof(seq));
+  sNTrace(pObj->data, "remove message handle, seq:%" PRIu64 " code:%d", seq, code);
 
-  taosThreadMutexUnlock(&(pObj->mutex));
-  return 0;
+  taosThreadMutexUnlock(&pObj->mutex);
+  return code;
 }
 
-int32_t syncRespMgrGet(SSyncRespMgr *pObj, uint64_t index, SRespStub *pStub) {
-  taosThreadMutexLock(&(pObj->mutex));
+int32_t syncRespMgrGet(SSyncRespMgr *pObj, uint64_t seq, SRespStub *pStub) {
+  taosThreadMutexLock(&pObj->mutex);
 
-  void *pTmp = taosHashGet(pObj->pRespHash, &index, sizeof(index));
+  SRespStub *pTmp = taosHashGet(pObj->pRespHash, &seq, sizeof(uint64_t));
   if (pTmp != NULL) {
     memcpy(pStub, pTmp, sizeof(SRespStub));
+    sNTrace(pObj->data, "get message handle, type:%s seq:%" PRIu64 " handle:%p", TMSG_INFO(pStub->rpcMsg.msgType), seq,
+            pStub->rpcMsg.info.handle);
 
-    sNTrace(pObj->data, "get message handle, type:%s seq:%" PRIu64 " handle:%p", TMSG_INFO(pStub->rpcMsg.msgType),
-            index, pStub->rpcMsg.info.handle);
-    taosThreadMutexUnlock(&(pObj->mutex));
+    taosThreadMutexUnlock(&pObj->mutex);
     return 1;  // get one object
   }
-  taosThreadMutexUnlock(&(pObj->mutex));
+
+  taosThreadMutexUnlock(&pObj->mutex);
   return 0;  // get none object
 }
 
-int32_t syncRespMgrGetAndDel(SSyncRespMgr *pObj, uint64_t index, SRespStub *pStub) {
-  taosThreadMutexLock(&(pObj->mutex));
+int32_t syncRespMgrGetAndDel(SSyncRespMgr *pObj, uint64_t seq, SRpcHandleInfo *pInfo) {
+  taosThreadMutexLock(&pObj->mutex);
 
-  void *pTmp = taosHashGet(pObj->pRespHash, &index, sizeof(index));
-  if (pTmp != NULL) {
-    memcpy(pStub, pTmp, sizeof(SRespStub));
+  SRespStub *pStub = taosHashGet(pObj->pRespHash, &seq, sizeof(uint64_t));
+  if (pStub != NULL) {
+    *pInfo = pStub->rpcMsg.info;
+    sNTrace(pObj->data, "get-and-del message handle:%p, type:%s seq:%" PRIu64, pStub->rpcMsg.info.handle,
+            TMSG_INFO(pStub->rpcMsg.msgType), seq);
+    taosHashRemove(pObj->pRespHash, &seq, sizeof(uint64_t));
 
-    sNTrace(pObj->data, "get-and-del message handle, type:%s seq:%" PRIu64 " handle:%p",
-            TMSG_INFO(pStub->rpcMsg.msgType), index, pStub->rpcMsg.info.handle);
-    taosHashRemove(pObj->pRespHash, &index, sizeof(index));
-    taosThreadMutexUnlock(&(pObj->mutex));
+    taosThreadMutexUnlock(&pObj->mutex);
     return 1;  // get one object
   }
-  taosThreadMutexUnlock(&(pObj->mutex));
-  return 0;  // get none object
-}
 
-void syncRespCleanRsp(SSyncRespMgr *pObj) {
-  taosThreadMutexLock(&(pObj->mutex));
-  syncRespCleanByTTL(pObj, -1, true);
-  taosThreadMutexUnlock(&(pObj->mutex));
-}
-
-void syncRespClean(SSyncRespMgr *pObj) {
-  taosThreadMutexLock(&(pObj->mutex));
-  syncRespCleanByTTL(pObj, pObj->ttl, false);
-  taosThreadMutexUnlock(&(pObj->mutex));
+  taosThreadMutexUnlock(&pObj->mutex);
+  return 0;  // get none object
 }
 
-void syncRespCleanByTTL(SSyncRespMgr *pObj, int64_t ttl, bool rsp) {
+static void syncRespCleanByTTL(SSyncRespMgr *pObj, int64_t ttl, bool rsp) {
   SRespStub *pStub = (SRespStub *)taosHashIterate(pObj->pRespHash, NULL);
   int        cnt = 0;
   int        sum = 0;
   SSyncNode *pSyncNode = pObj->data;
 
-  SArray *delIndexArray = taosArrayInit(0, sizeof(uint64_t));
-  ASSERT(delIndexArray != NULL);
-  sDebug("vgId:%d, resp mgr begin clean by ttl", pSyncNode->vgId);
+  SArray *delIndexArray = taosArrayInit(4, sizeof(uint64_t));
+  if (delIndexArray == NULL) return;
 
+  sDebug("vgId:%d, resp mgr begin clean by ttl", pSyncNode->vgId);
   while (pStub) {
     size_t    len;
-    void *    key = taosHashGetKey(pStub, &len);
+    void     *key = taosHashGetKey(pStub, &len);
     uint64_t *pSeqNum = (uint64_t *)key;
     sum++;
 
@@ -149,15 +141,15 @@ void syncRespCleanByTTL(SSyncRespMgr *pObj, int64_t ttl, bool rsp) {
       pStub->rpcMsg.contLen = 0;
 
       // TODO: and make rpcMsg body, call commit cb
-      // pSyncNode->pFsm->FpCommitCb(pSyncNode->pFsm, &(pStub->rpcMsg), cbMeta);
+      // pSyncNode->pFsm->FpCommitCb(pSyncNode->pFsm, &pStub->rpcMsg, cbMeta);
 
       pStub->rpcMsg.code = TSDB_CODE_SYN_NOT_LEADER;
       if (pStub->rpcMsg.info.handle != NULL) {
-        tmsgSendRsp(&(pStub->rpcMsg));
+        tmsgSendRsp(&pStub->rpcMsg);
       }
     }
 
-    pStub = (SRespStub *)taosHashIterate(pObj->pRespHash, pStub);
+    pStub = taosHashIterate(pObj->pRespHash, pStub);
   }
 
   int32_t arraySize = taosArrayGetSize(delIndexArray);
@@ -170,3 +162,15 @@ void syncRespCleanByTTL(SSyncRespMgr *pObj, int64_t ttl, bool rsp) {
   }
   taosArrayDestroy(delIndexArray);
 }
+
+void syncRespCleanRsp(SSyncRespMgr *pObj) {
+  taosThreadMutexLock(&pObj->mutex);
+  syncRespCleanByTTL(pObj, -1, true);
+  taosThreadMutexUnlock(&pObj->mutex);
+}
+
+void syncRespClean(SSyncRespMgr *pObj) {
+  taosThreadMutexLock(&pObj->mutex);
+  syncRespCleanByTTL(pObj, pObj->ttl, false);
+  taosThreadMutexUnlock(&pObj->mutex);
+}