diff --git a/source/dnode/mgmt/mgmt_mnode/src/mmWorker.c b/source/dnode/mgmt/mgmt_mnode/src/mmWorker.c
index 75d5669824..885086e37a 100644
--- a/source/dnode/mgmt/mgmt_mnode/src/mmWorker.c
+++ b/source/dnode/mgmt/mgmt_mnode/src/mmWorker.c
@@ -16,6 +16,8 @@
 #define _DEFAULT_SOURCE
 #include "mmInt.h"
 
+#define PROCESS_THRESHOLD (2000 * 1000)
+
 static inline int32_t mmAcquire(SMnodeMgmt *pMgmt) {
   int32_t code = 0;
   taosThreadRwlockRdlock(&pMgmt->lock);
@@ -53,6 +55,14 @@ static void mmProcessRpcMsg(SQueueInfo *pInfo, SRpcMsg *pMsg) {
 
   int32_t code = mndProcessRpcMsg(pMsg);
 
+  if (pInfo->timestamp != 0) {
+    int64_t cost = taosGetTimestampUs() - pInfo->timestamp;
+    if (cost > PROCESS_THRESHOLD) {
+      dGWarn("worker:%d,message has been processed for too long, type:%s, cost: %" PRId64 "s", pInfo->threadNum,
+             TMSG_INFO(pMsg->msgType), cost / (1000 * 1000));
+    }
+  }
+
   if (IsReq(pMsg) && pMsg->info.handle != NULL && code != TSDB_CODE_ACTION_IN_PROGRESS) {
     if (code != 0 && terrno != 0) code = terrno;
     mmSendRsp(pMsg, code);
diff --git a/source/dnode/mnode/impl/src/mndArbGroup.c b/source/dnode/mnode/impl/src/mndArbGroup.c
index 92ab5274e4..d0a86bdde7 100644
--- a/source/dnode/mnode/impl/src/mndArbGroup.c
+++ b/source/dnode/mnode/impl/src/mndArbGroup.c
@@ -27,6 +27,8 @@
 #define ARBGROUP_VER_NUMBER   1
 #define ARBGROUP_RESERVE_SIZE 64
 
+static SHashObj *arbUpdateHash = NULL;
+
 static int32_t mndArbGroupActionInsert(SSdb *pSdb, SArbGroup *pGroup);
 static int32_t mndArbGroupActionUpdate(SSdb *pSdb, SArbGroup *pOld, SArbGroup *pNew);
 static int32_t mndArbGroupActionDelete(SSdb *pSdb, SArbGroup *pGroup);
@@ -74,10 +76,14 @@ int32_t mndInitArbGroup(SMnode *pMnode) {
   mndAddShowRetrieveHandle(pMnode, TSDB_MGMT_TABLE_ARBGROUP, mndRetrieveArbGroups);
   mndAddShowFreeIterHandle(pMnode, TSDB_MGMT_TABLE_ARBGROUP, mndCancelGetNextArbGroup);
 
+  arbUpdateHash = taosHashInit(64, taosGetDefaultHashFunction(TSDB_DATA_TYPE_INT), false, HASH_ENTRY_LOCK);
+
   return sdbSetTable(pMnode->pSdb, table);
 }
 
-void mndCleanupArbGroup(SMnode *pMnode) {}
+void mndCleanupArbGroup(SMnode *pMnode) {
+  taosHashCleanup(arbUpdateHash);
+}
 
 SArbGroup *mndAcquireArbGroup(SMnode *pMnode, int32_t vgId) {
   SArbGroup *pGroup = sdbAcquire(pMnode->pSdb, SDB_ARBGROUP, &vgId);
@@ -221,8 +227,7 @@ static int32_t mndArbGroupActionUpdate(SSdb *pSdb, SArbGroup *pOld, SArbGroup *p
     mInfo("arbgroup:%d, skip to perform update action, old row:%p new row:%p, old version:%" PRId64
           " new version:%" PRId64,
           pOld->vgId, pOld, pNew, pOld->version, pNew->version);
-    taosThreadMutexUnlock(&pOld->mutex);
-    return 0;
+    goto _OVER;
   }
 
   for (int i = 0; i < TSDB_ARB_GROUP_MEMBER_NUM; i++) {
@@ -232,7 +237,11 @@ static int32_t mndArbGroupActionUpdate(SSdb *pSdb, SArbGroup *pOld, SArbGroup *p
   pOld->assignedLeader.dnodeId = pNew->assignedLeader.dnodeId;
   memcpy(pOld->assignedLeader.token, pNew->assignedLeader.token, TSDB_ARB_TOKEN_SIZE);
   pOld->version++;
+
+_OVER:
   taosThreadMutexUnlock(&pOld->mutex);
+
+  taosHashRemove(arbUpdateHash, &pOld->vgId, sizeof(int32_t));
   return 0;
 }
 
@@ -645,6 +654,11 @@ static void *mndBuildArbUpdateGroupReq(int32_t *pContLen, SArbGroup *pNewGroup)
 }
 
 static int32_t mndPullupArbUpdateGroup(SMnode *pMnode, SArbGroup *pNewGroup) {
+  if (taosHashGet(arbUpdateHash, &pNewGroup->vgId, sizeof(pNewGroup->vgId)) != NULL) {
+    mInfo("vgId:%d, arb skip to pullup arb-update-group request, since it is in process", pNewGroup->vgId);
+    return 0;
+  }
+
   int32_t contLen = 0;
   void   *pHead = mndBuildArbUpdateGroupReq(&contLen, pNewGroup);
   if (!pHead) {
@@ -653,7 +667,11 @@ static int32_t mndPullupArbUpdateGroup(SMnode *pMnode, SArbGroup *pNewGroup) {
   }
   SRpcMsg rpcMsg = {.msgType = TDMT_MND_ARB_UPDATE_GROUP, .pCont = pHead, .contLen = contLen, .info.noResp = true};
 
-  return tmsgPutToQueue(&pMnode->msgCb, WRITE_QUEUE, &rpcMsg);
+  int32_t ret = tmsgPutToQueue(&pMnode->msgCb, WRITE_QUEUE, &rpcMsg);
+  if (ret == 0) {
+    taosHashPut(arbUpdateHash, &pNewGroup->vgId, sizeof(pNewGroup->vgId), NULL, 0);
+  }
+  return ret;
 }
 
 static int32_t mndProcessArbUpdateGroupReq(SRpcMsg *pReq) {
@@ -930,8 +948,12 @@ static int32_t mndProcessArbCheckSyncRsp(SRpcMsg *pRsp) {
 
   SVArbCheckSyncRsp syncRsp = {0};
   if (tDeserializeSVArbCheckSyncRsp(pRsp->pCont, pRsp->contLen, &syncRsp) != 0) {
-    terrno = TSDB_CODE_INVALID_MSG;
     mInfo("arb sync check failed, since:%s", tstrerror(pRsp->code));
+    if (pRsp->code == TSDB_CODE_MND_ARB_TOKEN_MISMATCH) {
+      terrno = TSDB_CODE_SUCCESS;
+      return 0;
+    }
+    terrno = TSDB_CODE_INVALID_MSG;
     return -1;
   }