diff --git a/source/libs/sync/src/syncAppendEntriesReply.c b/source/libs/sync/src/syncAppendEntriesReply.c
index 94c4de3c5e75da0ae0ce1e87521bd85a95482884..875204c0a9799386c069872b6d9a9aace85fb230 100644
--- a/source/libs/sync/src/syncAppendEntriesReply.c
+++ b/source/libs/sync/src/syncAppendEntriesReply.c
@@ -37,43 +37,6 @@
 //    /\ UNCHANGED <<serverVars, candidateVars, logVars, elections>>
 //
 
-// only start once
-static void syncNodeStartSnapshotOnce(SSyncNode* ths, SyncIndex beginIndex, SyncIndex endIndex, SyncTerm lastApplyTerm,
-                                      SyncAppendEntriesReply* pMsg) {
-  if (beginIndex > endIndex) {
-    sNError(ths, "snapshot param error, start:%" PRId64 ", end:%" PRId64, beginIndex, endIndex);
-    return;
-  }
-
-  // get sender
-  SSyncSnapshotSender* pSender = syncNodeGetSnapshotSender(ths, &(pMsg->srcId));
-  ASSERT(pSender != NULL);
-
-  if (snapshotSenderIsStart(pSender)) {
-    sSError(pSender, "snapshot sender already start");
-    return;
-  }
-
-  SSnapshot snapshot = {
-      .data = NULL, .lastApplyIndex = endIndex, .lastApplyTerm = lastApplyTerm, .lastConfigIndex = SYNC_INDEX_INVALID};
-  void*          pReader = NULL;
-  SSnapshotParam readerParam = {.start = beginIndex, .end = endIndex};
-  int32_t        code = ths->pFsm->FpSnapshotStartRead(ths->pFsm, &readerParam, &pReader);
-  ASSERT(code == 0);
-
-#if 0
-  if (pMsg->privateTerm < pSender->privateTerm) {
-    ASSERT(pReader != NULL);
-    snapshotSenderStart(pSender, readerParam, snapshot, pReader);
-
-  } else {
-    if (pReader != NULL) {
-      ths->pFsm->FpSnapshotStopRead(ths->pFsm, pReader);
-    }
-  }
-#endif
-}
-
 int32_t syncNodeOnAppendEntriesReply(SSyncNode* ths, const SRpcMsg* pRpcMsg) {
   int32_t                 ret = 0;
   SyncAppendEntriesReply* pMsg = pRpcMsg->pCont;
diff --git a/source/libs/sync/src/syncMain.c b/source/libs/sync/src/syncMain.c
index 5ceca36aaca602e5fee01f6d040316d48c86e562..8bccf6840a37d4fd8c4a6fb42f02fed24753358a 100644
--- a/source/libs/sync/src/syncMain.c
+++ b/source/libs/sync/src/syncMain.c
@@ -385,7 +385,7 @@ bool syncIsReadyForRead(int64_t rid) {
       if (!pSyncNode->pLogStore->syncLogIsEmpty(pSyncNode->pLogStore)) {
         SSyncRaftEntry* pEntry = NULL;
         int32_t         code = pSyncNode->pLogStore->syncLogGetEntry(
-                    pSyncNode->pLogStore, pSyncNode->pLogStore->syncLogLastIndex(pSyncNode->pLogStore), &pEntry);
+            pSyncNode->pLogStore, pSyncNode->pLogStore->syncLogLastIndex(pSyncNode->pLogStore), &pEntry);
         if (code == 0 && pEntry != NULL) {
           if (pEntry->originalRpcType == TDMT_SYNC_NOOP && pEntry->term == pSyncNode->pRaftStore->currentTerm) {
             ready = true;
diff --git a/source/libs/sync/src/syncRaftLog.c b/source/libs/sync/src/syncRaftLog.c
index 7e4b18ab886fd8993a79ae06f9dab16d5b64d1cb..bc07781e5c2577668c58b246f8157dcceb36c95b 100644
--- a/source/libs/sync/src/syncRaftLog.c
+++ b/source/libs/sync/src/syncRaftLog.c
@@ -197,7 +197,12 @@ static int32_t raftLogAppendEntry(struct SSyncLogStore* pLogStore, SSyncRaftEntr
   syncMeta.isWeek = pEntry->isWeak;
   syncMeta.seqNum = pEntry->seqNum;
   syncMeta.term = pEntry->term;
+
+  int64_t tsWriteBegin = taosGetTimestampMs();
   index = walAppendLog(pWal, pEntry->originalRpcType, syncMeta, pEntry->data, pEntry->dataLen);
+  int64_t tsWriteEnd = taosGetTimestampMs();
+  int64_t tsElapsed = tsWriteEnd - tsWriteBegin;
+
   if (index < 0) {
     int32_t     err = terrno;
     const char* errStr = tstrerror(err);
@@ -210,8 +215,8 @@ static int32_t raftLogAppendEntry(struct SSyncLogStore* pLogStore, SSyncRaftEntr
   }
   pEntry->index = index;
 
-  sNTrace(pData->pSyncNode, "write index:%" PRId64 ", type:%s, origin type:%s", pEntry->index,
-          TMSG_INFO(pEntry->msgType), TMSG_INFO(pEntry->originalRpcType));
+  sNTrace(pData->pSyncNode, "write index:%" PRId64 ", type:%s, origin type:%s, elapsed:%" PRId64, pEntry->index,
+          TMSG_INFO(pEntry->msgType), TMSG_INFO(pEntry->originalRpcType), tsElapsed);
   return 0;
 }
 
@@ -236,7 +241,11 @@ int32_t raftLogGetEntry(struct SSyncLogStore* pLogStore, SyncIndex index, SSyncR
 
   taosThreadMutexLock(&(pData->mutex));
 
+  int64_t tsBegin = taosGetTimestampMs();
   code = walReadVer(pWalHandle, index);
+  int64_t tsEnd = taosGetTimestampMs();
+  int64_t tsElapsed = tsEnd - tsBegin;
+
   // code = walReadVerCached(pWalHandle, index);
   if (code != 0) {
     int32_t     err = terrno;
diff --git a/source/libs/sync/src/syncReplication.c b/source/libs/sync/src/syncReplication.c
index f09bac21396cd0bb4a56c0fbac46176f605ea457..59afe814ebcae0b6ad029201a5100f7120c3c9c5 100644
--- a/source/libs/sync/src/syncReplication.c
+++ b/source/libs/sync/src/syncReplication.c
@@ -140,9 +140,10 @@ int32_t syncNodeReplicate(SSyncNode* pSyncNode) {
 int32_t syncNodeSendAppendEntries(SSyncNode* pSyncNode, const SRaftId* destRaftId, SRpcMsg* pRpcMsg) {
   int32_t            ret = 0;
   SyncAppendEntries* pMsg = pRpcMsg->pCont;
-
-  syncLogSendAppendEntries(pSyncNode, pMsg, "");
-  syncNodeSendMsgById(destRaftId, pSyncNode, pRpcMsg);
+  if (pMsg == NULL) {
+    sError("vgId:%d, sync-append-entries msg is NULL", pSyncNode->vgId);
+    return 0;
+  }
 
   SPeerState* pState = syncNodeGetPeerState(pSyncNode, destRaftId);
   if (pState == NULL) {
@@ -150,8 +151,19 @@ int32_t syncNodeSendAppendEntries(SSyncNode* pSyncNode, const SRaftId* destRaftI
     return 0;
   }
 
+  // save index, otherwise pMsg will be free by rpc
+  SyncIndex saveLastSendIndex = pState->lastSendIndex;
+  bool      update = false;
   if (pMsg->dataLen > 0) {
-    pState->lastSendIndex = pMsg->prevLogIndex + 1;
+    saveLastSendIndex = pMsg->prevLogIndex + 1;
+    update = true;
+  }
+
+  syncLogSendAppendEntries(pSyncNode, pMsg, "");
+  syncNodeSendMsgById(destRaftId, pSyncNode, pRpcMsg);
+
+  if (update) {
+    pState->lastSendIndex = saveLastSendIndex;
     pState->lastSendTime = taosGetTimestampMs();
   }