diff --git a/source/dnode/mnode/impl/src/mndConsumer.c b/source/dnode/mnode/impl/src/mndConsumer.c
index 76b8081849f41edd09d576b1fb79608b4094c50c..820c25f1f228a858117f57971571ce855265c64b 100644
--- a/source/dnode/mnode/impl/src/mndConsumer.c
+++ b/source/dnode/mnode/impl/src/mndConsumer.c
@@ -135,16 +135,18 @@ FAIL:
 }
 
 static SMqRebInfo *mndGetOrCreateRebSub(SHashObj *pHash, const char *key) {
-  SMqRebInfo *pRebSub = taosHashGet(pHash, key, strlen(key) + 1);
-  if (pRebSub == NULL) {
-    pRebSub = tNewSMqRebSubscribe(key);
-    if (pRebSub == NULL) {
+  SMqRebInfo *pRebInfo = taosHashGet(pHash, key, strlen(key) + 1);
+  if (pRebInfo == NULL) {
+    pRebInfo = tNewSMqRebSubscribe(key);
+    if (pRebInfo == NULL) {
       terrno = TSDB_CODE_OUT_OF_MEMORY;
       return NULL;
     }
-    taosHashPut(pHash, key, strlen(key) + 1, pRebSub, sizeof(SMqRebInfo));
+    taosHashPut(pHash, key, strlen(key) + 1, pRebInfo, sizeof(SMqRebInfo));
+    taosMemoryFree(pRebInfo);
+    pRebInfo = taosHashGet(pHash, key, strlen(key) + 1);
   }
-  return pRebSub;
+  return pRebInfo;
 }
 
 static int32_t mndProcessMqTimerMsg(SNodeMsg *pMsg) {
@@ -305,8 +307,10 @@ static int32_t mndProcessAskEpReq(SNodeMsg *pMsg) {
       ASSERT(pTopic);
       taosRLockLatch(&pTopic->lock);
       topicEp.schema.nCols = pTopic->schema.nCols;
-      topicEp.schema.pSchema = taosMemoryCalloc(topicEp.schema.nCols, sizeof(SSchema));
-      memcpy(topicEp.schema.pSchema, pTopic->schema.pSchema, topicEp.schema.nCols * sizeof(SSchema));
+      if (topicEp.schema.nCols) {
+        topicEp.schema.pSchema = taosMemoryCalloc(topicEp.schema.nCols, sizeof(SSchema));
+        memcpy(topicEp.schema.pSchema, pTopic->schema.pSchema, topicEp.schema.nCols * sizeof(SSchema));
+      }
       taosRUnLockLatch(&pTopic->lock);
       mndReleaseTopic(pMnode, pTopic);
 
@@ -517,6 +521,7 @@ SUBSCRIBE_OVER:
   }
   if (pConsumerNew) {
     tDeleteSMqConsumerObj(pConsumerNew);
+    taosMemoryFree(pConsumerNew);
   }
   // TODO: replace with destroy subscribe msg
   if (subscribe.topicNames) taosArrayDestroyP(subscribe.topicNames, (FDelete)taosMemoryFree);
diff --git a/source/dnode/mnode/impl/src/mndSubscribe.c b/source/dnode/mnode/impl/src/mndSubscribe.c
index 3e932e8a67db896d83314c78c0f259daf2af480d..9aee411ece8b9682acc35c98793349a3de318105 100644
--- a/source/dnode/mnode/impl/src/mndSubscribe.c
+++ b/source/dnode/mnode/impl/src/mndSubscribe.c
@@ -502,9 +502,9 @@ static int32_t mndProcessRebalanceReq(SNodeMsg *pMsg) {
     SMqRebInputObj rebInput = {0};
 
     SMqRebOutputObj rebOutput = {0};
-    rebOutput.newConsumers = taosArrayInit(0, sizeof(void *));
-    rebOutput.removedConsumers = taosArrayInit(0, sizeof(void *));
-    rebOutput.touchedConsumers = taosArrayInit(0, sizeof(void *));
+    rebOutput.newConsumers = taosArrayInit(0, sizeof(int64_t));
+    rebOutput.removedConsumers = taosArrayInit(0, sizeof(int64_t));
+    rebOutput.touchedConsumers = taosArrayInit(0, sizeof(int64_t));
     rebOutput.rebVgs = taosArrayInit(0, sizeof(SMqRebOutputVg));
 
     SMqRebInfo      *pRebInfo = (SMqRebInfo *)pIter;
@@ -547,6 +547,16 @@ static int32_t mndProcessRebalanceReq(SNodeMsg *pMsg) {
     if (mndPersistRebResult(pMnode, pMsg, &rebOutput) < 0) {
       mError("persist rebalance output error, possibly vnode splitted or dropped");
     }
+    taosArrayDestroy(pRebInfo->lostConsumers);
+    taosArrayDestroy(pRebInfo->newConsumers);
+    taosArrayDestroy(pRebInfo->removedConsumers);
+
+    taosArrayDestroy(rebOutput.newConsumers);
+    taosArrayDestroy(rebOutput.touchedConsumers);
+    taosArrayDestroy(rebOutput.removedConsumers);
+    taosArrayDestroy(rebOutput.rebVgs);
+    tDeleteSubscribeObj(rebOutput.pSub);
+    taosMemoryFree(rebOutput.pSub);
   }
 
   // reset flag
diff --git a/source/dnode/mnode/impl/src/mndTopic.c b/source/dnode/mnode/impl/src/mndTopic.c
index bc650ec95b60f94bb9227a53d938dde52d79ac4c..2d9681f5433d3b05efaf975beb373c5c8077e2a0 100644
--- a/source/dnode/mnode/impl/src/mndTopic.c
+++ b/source/dnode/mnode/impl/src/mndTopic.c
@@ -72,8 +72,15 @@ const char *mndTopicGetShowName(const char topic[TSDB_TOPIC_FNAME_LEN]) {
 SSdbRaw *mndTopicActionEncode(SMqTopicObj *pTopic) {
   terrno = TSDB_CODE_OUT_OF_MEMORY;
 
-  int32_t physicalPlanLen = strlen(pTopic->physicalPlan) + 1;
-  int32_t schemaLen = taosEncodeSSchemaWrapper(NULL, &pTopic->schema);
+  void   *swBuf = NULL;
+  int32_t physicalPlanLen = 0;
+  if (pTopic->physicalPlan) {
+    physicalPlanLen = strlen(pTopic->physicalPlan) + 1;
+  }
+  int32_t schemaLen = 0;
+  if (pTopic->schema.nCols) {
+    taosEncodeSSchemaWrapper(NULL, &pTopic->schema);
+  }
   int32_t size =
       sizeof(SMqTopicObj) + physicalPlanLen + pTopic->sqlLen + pTopic->astLen + schemaLen + MND_TOPIC_RESERVE_SIZE;
   SSdbRaw *pRaw = sdbAllocRaw(SDB_TOPIC, MND_TOPIC_VER_NUMBER, size);
@@ -96,18 +103,24 @@ SSdbRaw *mndTopicActionEncode(SMqTopicObj *pTopic) {
   SDB_SET_INT32(pRaw, dataPos, pTopic->sqlLen, TOPIC_ENCODE_OVER);
   SDB_SET_BINARY(pRaw, dataPos, pTopic->sql, pTopic->sqlLen, TOPIC_ENCODE_OVER);
   SDB_SET_INT32(pRaw, dataPos, pTopic->astLen, TOPIC_ENCODE_OVER);
-  SDB_SET_BINARY(pRaw, dataPos, pTopic->ast, pTopic->astLen, TOPIC_ENCODE_OVER);
+  if (pTopic->astLen) {
+    SDB_SET_BINARY(pRaw, dataPos, pTopic->ast, pTopic->astLen, TOPIC_ENCODE_OVER);
+  }
   SDB_SET_INT32(pRaw, dataPos, physicalPlanLen, TOPIC_ENCODE_OVER);
-  SDB_SET_BINARY(pRaw, dataPos, pTopic->physicalPlan, physicalPlanLen, TOPIC_ENCODE_OVER);
-
-  void *swBuf = taosMemoryMalloc(schemaLen);
-  if (swBuf == NULL) {
-    goto TOPIC_ENCODE_OVER;
+  if (physicalPlanLen) {
+    SDB_SET_BINARY(pRaw, dataPos, pTopic->physicalPlan, physicalPlanLen, TOPIC_ENCODE_OVER);
   }
-  void *aswBuf = swBuf;
-  taosEncodeSSchemaWrapper(&aswBuf, &pTopic->schema);
   SDB_SET_INT32(pRaw, dataPos, schemaLen, TOPIC_ENCODE_OVER);
-  SDB_SET_BINARY(pRaw, dataPos, swBuf, schemaLen, TOPIC_ENCODE_OVER);
+  if (schemaLen) {
+    swBuf = taosMemoryMalloc(schemaLen);
+    if (swBuf == NULL) {
+      goto TOPIC_ENCODE_OVER;
+    }
+    void *aswBuf = swBuf;
+    taosEncodeSSchemaWrapper(&aswBuf, &pTopic->schema);
+    SDB_SET_BINARY(pRaw, dataPos, swBuf, schemaLen, TOPIC_ENCODE_OVER);
+  }
+
   SDB_SET_INT32(pRaw, dataPos, pTopic->refConsumerCnt, TOPIC_ENCODE_OVER);
 
   SDB_SET_RESERVE(pRaw, dataPos, MND_TOPIC_RESERVE_SIZE, TOPIC_ENCODE_OVER);
@@ -116,6 +129,7 @@ SSdbRaw *mndTopicActionEncode(SMqTopicObj *pTopic) {
   terrno = TSDB_CODE_SUCCESS;
 
 TOPIC_ENCODE_OVER:
+  if (swBuf) taosMemoryFree(swBuf);
   if (terrno != TSDB_CODE_SUCCESS) {
     mError("topic:%s, failed to encode to raw:%p since %s", pTopic->name, pRaw, terrstr());
     sdbFreeRaw(pRaw);
@@ -168,29 +182,43 @@ SSdbRow *mndTopicActionDecode(SSdbRaw *pRaw) {
   SDB_GET_BINARY(pRaw, dataPos, pTopic->sql, pTopic->sqlLen, TOPIC_DECODE_OVER);
 
   SDB_GET_INT32(pRaw, dataPos, &pTopic->astLen, TOPIC_DECODE_OVER);
-  pTopic->ast = taosMemoryCalloc(pTopic->astLen, sizeof(char));
-  if (pTopic->ast == NULL) {
-    terrno = TSDB_CODE_OUT_OF_MEMORY;
-    goto TOPIC_DECODE_OVER;
+  if (pTopic->astLen) {
+    pTopic->ast = taosMemoryCalloc(pTopic->astLen, sizeof(char));
+    if (pTopic->ast == NULL) {
+      terrno = TSDB_CODE_OUT_OF_MEMORY;
+      goto TOPIC_DECODE_OVER;
+    }
+  } else {
+    pTopic->ast = NULL;
   }
   SDB_GET_BINARY(pRaw, dataPos, pTopic->ast, pTopic->astLen, TOPIC_DECODE_OVER);
   SDB_GET_INT32(pRaw, dataPos, &len, TOPIC_DECODE_OVER);
-  pTopic->physicalPlan = taosMemoryCalloc(len, sizeof(char));
-  if (pTopic->physicalPlan == NULL) {
-    terrno = TSDB_CODE_OUT_OF_MEMORY;
-    goto TOPIC_DECODE_OVER;
+  if (len) {
+    pTopic->physicalPlan = taosMemoryCalloc(len, sizeof(char));
+    if (pTopic->physicalPlan == NULL) {
+      terrno = TSDB_CODE_OUT_OF_MEMORY;
+      goto TOPIC_DECODE_OVER;
+    }
+    SDB_GET_BINARY(pRaw, dataPos, pTopic->physicalPlan, len, TOPIC_DECODE_OVER);
+  } else {
+    pTopic->physicalPlan = NULL;
   }
-  SDB_GET_BINARY(pRaw, dataPos, pTopic->physicalPlan, len, TOPIC_DECODE_OVER);
 
   SDB_GET_INT32(pRaw, dataPos, &len, TOPIC_DECODE_OVER);
-  void *buf = taosMemoryMalloc(len);
-  if (buf == NULL) {
-    terrno = TSDB_CODE_OUT_OF_MEMORY;
-    goto TOPIC_DECODE_OVER;
-  }
-  SDB_GET_BINARY(pRaw, dataPos, buf, len, TOPIC_DECODE_OVER);
-  if (taosDecodeSSchemaWrapper(buf, &pTopic->schema) == NULL) {
-    goto TOPIC_DECODE_OVER;
+  if (len) {
+    void *buf = taosMemoryMalloc(len);
+    if (buf == NULL) {
+      terrno = TSDB_CODE_OUT_OF_MEMORY;
+      goto TOPIC_DECODE_OVER;
+    }
+    SDB_GET_BINARY(pRaw, dataPos, buf, len, TOPIC_DECODE_OVER);
+    if (taosDecodeSSchemaWrapper(buf, &pTopic->schema) == NULL) {
+      goto TOPIC_DECODE_OVER;
+    }
+  } else {
+    pTopic->schema.nCols = 0;
+    pTopic->schema.sver = 0;
+    pTopic->schema.pSchema = NULL;
   }
 
   SDB_GET_INT32(pRaw, dataPos, &pTopic->refConsumerCnt, TOPIC_DECODE_OVER);
@@ -340,9 +368,9 @@ static int32_t mndCreateTopic(SMnode *pMnode, SNodeMsg *pReq, SCMCreateTopicReq
       return -1;
     }
   } else {
-    topicObj.ast = strdup("");
-    topicObj.astLen = 1;
-    topicObj.physicalPlan = strdup("");
+    topicObj.ast = NULL;
+    topicObj.astLen = 0;
+    topicObj.physicalPlan = NULL;
     topicObj.subType = TOPIC_SUB_TYPE__DB;
     topicObj.withTbName = 1;
     topicObj.withSchema = 1;
diff --git a/source/dnode/vnode/src/tq/tq.c b/source/dnode/vnode/src/tq/tq.c
index bc9893b8a0710ffac8fdb7f143a6279b00de1050..6cc986d54bfc5856c6d439eb03078307a1a70ef2 100644
--- a/source/dnode/vnode/src/tq/tq.c
+++ b/source/dnode/vnode/src/tq/tq.c
@@ -613,6 +613,7 @@ int32_t tqProcessPollReq(STQ* pTq, SRpcMsg* pMsg, int32_t workerId) {
     fetchOffset++;
   }
 
+  taosMemoryFree(pHeadWithCkSum);
   ASSERT(taosArrayGetSize(rsp.blockData) == rsp.blockNum);
   ASSERT(taosArrayGetSize(rsp.blockDataLen) == rsp.blockNum);