diff --git a/include/client/taos.h b/include/client/taos.h
index 84f625571095e519b3268d42324719461d5ac650..40772e9d2c4e201b261fbc2481a90a1bb48da83b 100644
--- a/include/client/taos.h
+++ b/include/client/taos.h
@@ -192,9 +192,38 @@ DLL_EXPORT void taos_close_stream(TAOS_STREAM *tstr);
 
 DLL_EXPORT int taos_load_table_info(TAOS *taos, const char* tableNameList);
 DLL_EXPORT TAOS_RES* taos_schemaless_insert(TAOS* taos, char* lines[], int numLines, int protocol, int precision);
+typedef struct tmq_t tmq_t;
+typedef struct tmq_conf_t tmq_conf_t;
+typedef struct tmq_list_t tmq_list_t;
+
+typedef struct tmq_message_t       tmq_message_t;
+typedef struct tmq_message_topic_t tmq_message_topic_t;
+typedef struct tmq_message_tb_t    tmq_message_tb_t;
+typedef struct tmq_tb_iter_t       tmq_tb_iter_t;
+typedef struct tmq_message_col_t   tmq_message_col_t;
+typedef struct tmq_col_iter_t      tmq_col_iter_t;
+
+DLL_EXPORT tmq_list_t* tmq_list_new();
+DLL_EXPORT int32_t tmq_list_append(tmq_list_t*, char*);
+
+DLL_EXPORT tmq_conf_t* tmq_conf_new();
+
+DLL_EXPORT int32_t tmq_conf_set(tmq_conf_t* conf, const char* key, const char* value);
 
 DLL_EXPORT TAOS_RES *taos_create_topic(TAOS* taos, const char* name, const char* sql, int sqlLen);
 
+DLL_EXPORT tmq_t* taos_consumer_new(void* conn, tmq_conf_t* conf, char* errstr, int32_t errstrLen);
+
+DLL_EXPORT TAOS_RES* tmq_subscribe(tmq_t* tmq, tmq_list_t* topic_list);
+
+DLL_EXPORT tmq_message_t* tmq_consume_poll(tmq_t* tmq, int64_t blocking_time);
+
+DLL_EXPORT int32_t tmq_topic_num(tmq_message_t* msg);
+DLL_EXPORT char* tmq_get_topic(tmq_message_topic_t* msg);
+DLL_EXPORT int32_t tmq_get_vgId(tmq_message_topic_t* msg);
+DLL_EXPORT tmq_message_tb_t* tmq_get_next_tb(tmq_message_topic_t* msg, tmq_tb_iter_t* iter);
+DLL_EXPORT tmq_message_col_t* tmq_get_next_col(tmq_message_tb_t* msg, tmq_col_iter_t* iter);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/include/common/tmsg.h b/include/common/tmsg.h
index 857de3671f49f07f5ba2f6e2b48cdb35e06ffb42..7630c5f5e5830dbac553d493f9d21a3a7d421f9e 100644
--- a/include/common/tmsg.h
+++ b/include/common/tmsg.h
@@ -1519,7 +1519,8 @@ static FORCE_INLINE void* taosDecodeSMqMsg(void* buf, SMqHbMsg* pMsg) {
 
 typedef struct SMqSetCVgReq {
   int32_t vgId;
-  int64_t consumerId;
+  int64_t oldConsumerId;
+  int64_t newConsumerId;
   char    topicName[TSDB_TOPIC_FNAME_LEN];
   char    cgroup[TSDB_CONSUMER_GROUP_LEN];
   char*   sql;
@@ -1550,7 +1551,8 @@ static FORCE_INLINE void* tDecodeSSubQueryMsg(void* buf, SSubQueryMsg* pMsg) {
 static FORCE_INLINE int32_t tEncodeSMqSetCVgReq(void** buf, const SMqSetCVgReq* pReq) {
   int32_t tlen = 0;
   tlen += taosEncodeFixedI32(buf, pReq->vgId);
-  tlen += taosEncodeFixedI64(buf, pReq->consumerId);
+  tlen += taosEncodeFixedI64(buf, pReq->oldConsumerId);
+  tlen += taosEncodeFixedI64(buf, pReq->newConsumerId);
   tlen += taosEncodeString(buf, pReq->topicName);
   tlen += taosEncodeString(buf, pReq->cgroup);
   tlen += taosEncodeString(buf, pReq->sql);
@@ -1562,7 +1564,8 @@ static FORCE_INLINE int32_t tEncodeSMqSetCVgReq(void** buf, const SMqSetCVgReq*
 
 static FORCE_INLINE void* tDecodeSMqSetCVgReq(void* buf, SMqSetCVgReq* pReq) {
   buf = taosDecodeFixedI32(buf, &pReq->vgId);
-  buf = taosDecodeFixedI64(buf, &pReq->consumerId);
+  buf = taosDecodeFixedI64(buf, &pReq->oldConsumerId);
+  buf = taosDecodeFixedI64(buf, &pReq->newConsumerId);
   buf = taosDecodeStringTo(buf, pReq->topicName);
   buf = taosDecodeStringTo(buf, pReq->cgroup);
   buf = taosDecodeString(buf, &pReq->sql);
@@ -1579,15 +1582,6 @@ typedef struct SMqSetCVgRsp {
   char    cGroup[TSDB_CONSUMER_GROUP_LEN];
 } SMqSetCVgRsp;
 
-typedef struct SMqConsumeReq {
-  int64_t reqId;
-  int64_t offset;
-  int64_t consumerId;
-  int64_t blockingTime;
-  char    topicName[TSDB_TOPIC_FNAME_LEN];
-  char    cgroup[TSDB_CONSUMER_GROUP_LEN];
-} SMqConsumeReq;
-
 typedef struct SMqColData {
   int16_t colId;
   int16_t type;
@@ -1615,12 +1609,29 @@ typedef struct SMqTopicBlk {
 
 typedef struct SMqConsumeRsp {
   int64_t      reqId;
-  int64_t      clientId;
+  int64_t      consumerId;
   int32_t      bodyLen;
   int32_t      numOfTopics;
   SMqTopicData data[];
 } SMqConsumeRsp;
 
+// one req for one vg+topic
+typedef struct SMqConsumeReq {
+  //0: commit only, current offset
+  //1: consume only, poll next offset
+  //2: commit current and consume next offset
+  int32_t        reqType;
+
+  int64_t        reqId;
+  int64_t        consumerId;
+  int64_t        blockingTime;
+  char           cgroup[TSDB_CONSUMER_GROUP_LEN];
+
+  int64_t        offset;
+  char           topic[TSDB_TOPIC_FNAME_LEN];
+} SMqConsumeReq;
+
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/client/src/clientImpl.c b/source/client/src/clientImpl.c
index 23e2045a881296ed7a1a537af7ce1a6989807743..b0b3d031b28270fa8f7d3a9f865b104d5c0016bc 100644
--- a/source/client/src/clientImpl.c
+++ b/source/client/src/clientImpl.c
@@ -117,7 +117,7 @@ TAOS *taos_connect_internal(const char *ip, const char *user, const char *pass,
     SAppInstInfo* p = calloc(1, sizeof(struct SAppInstInfo));
     p->mgmtEp       = epSet;
     p->pTransporter = openTransporter(user, secretEncrypt, tsNumOfCores);
-    /*p->pAppHbMgr = appHbMgrInit(p);*/
+    p->pAppHbMgr = appHbMgrInit(p);
     taosHashPut(appInfo.pInstMap, key, strlen(key), &p, POINTER_BYTES);
 
     pInst = &p;
@@ -254,14 +254,8 @@ int32_t scheduleQuery(SRequestObj* pRequest, SQueryDag* pDag, SArray* pNodeList)
   return schedulerAsyncExecJob(pRequest->pTscObj->pAppInfo->pTransporter, pNodeList, pDag, &pRequest->body.pQueryJob);
 }
 
-typedef struct tmq_t tmq_t;
 
-typedef struct SMqClientTopic {
-  // subscribe info
-  int32_t sqlLen;
-  char*   sql;
-  char*   topicName;
-  int64_t topicId;
+typedef struct SMqClientVg {
   // statistics
   int64_t consumeCnt;
   // offset
@@ -270,35 +264,159 @@ typedef struct SMqClientTopic {
   //connection info
   int32_t vgId;
   SEpSet  epSet;
+} SMqClientVg;
+
+typedef struct SMqClientTopic {
+  // subscribe info
+  int32_t sqlLen;
+  char*   sql;
+  char*   topicName;
+  int64_t topicId;
+  int32_t nextVgIdx;
+  SArray* vgs;    //SArray<SMqClientVg>
 } SMqClientTopic;
 
 typedef struct tmq_resp_err_t {
   int32_t code;
 } tmq_resp_err_t;
 
-typedef struct tmq_topic_vgroup_list_t {
-  char* topicName;
+typedef struct tmq_topic_vgroup_t {
+  char*   topic;
   int32_t vgId;
-  int64_t committedOffset;
+  int64_t commitOffset;
+} tmq_topic_vgroup_t;
+
+typedef struct tmq_topic_vgroup_list_t {
+  int32_t cnt;
+  int32_t size;
+  tmq_topic_vgroup_t* elems;
 } tmq_topic_vgroup_list_t;
 
 typedef void (tmq_commit_cb(tmq_t*, tmq_resp_err_t, tmq_topic_vgroup_list_t*, void* param));
 
-typedef struct tmq_conf_t{
-  char*          clientId;
-  char*          groupId;
+struct tmq_conf_t {
+  char           clientId[256];
+  char           groupId[256];
   char*          ip;
   uint16_t       port;
   tmq_commit_cb* commit_cb;
-} tmq_conf_t;
+};
+
+tmq_conf_t* tmq_conf_new() {
+  tmq_conf_t* conf = calloc(1, sizeof(tmq_conf_t));
+  return conf;
+}
+
+int32_t tmq_conf_set(tmq_conf_t* conf, const char* key, const char* value) {
+  if (strcmp(key, "group.id")) {
+    strcpy(conf->groupId, value);
+  }
+  if (strcmp(key, "client.id")) {
+    strcpy(conf->clientId, value);
+  }
+  return 0;
+}
 
 struct tmq_t {
   char           groupId[256];
   char           clientId[256];
+  int64_t        consumerId;
+  int64_t        status;
   STscObj*       pTscObj;
   tmq_commit_cb* commit_cb;
-  SArray*        clientTopics;  // SArray<SMqClientTopic>
+  int32_t        nextTopicIdx;
+  SArray*        clientTopics;  //SArray<SMqClientTopic>
+};
+
+tmq_t* taos_consumer_new(void* conn, tmq_conf_t* conf, char* errstr, int32_t errstrLen) {
+  tmq_t* pTmq = calloc(sizeof(tmq_t), 1);
+  if (pTmq == NULL) {
+    return NULL;
+  }
+  pTmq->pTscObj = (STscObj*)conn;
+  pTmq->status = 0;
+  strcpy(pTmq->clientId, conf->clientId);
+  strcpy(pTmq->groupId, conf->groupId);
+  pTmq->commit_cb = conf->commit_cb;
+  pTmq->consumerId = generateRequestId() & ((uint64_t)-1 >> 1);
+  return pTmq;
+}
+
+struct tmq_list_t {
+  int32_t cnt;
+  int32_t tot;
+  char*   elems[];
 };
+tmq_list_t* tmq_list_new() {
+  tmq_list_t *ptr = malloc(sizeof(tmq_list_t) + 8 * sizeof(char*));
+  if (ptr == NULL) {
+    return ptr;
+  }
+  ptr->cnt = 0;
+  ptr->tot = 8;
+  return ptr;
+}
+
+int32_t tmq_list_append(tmq_list_t* ptr, char* src) {
+  if (ptr->cnt >= ptr->tot-1) return -1;
+  ptr->elems[ptr->cnt] = src;
+  ptr->cnt++;
+  return 0;
+}
+
+
+TAOS_RES* tmq_subscribe(tmq_t* tmq, tmq_list_t* topic_list) {
+  SRequestObj *pRequest = NULL;
+  tmq->status = 1;
+  int32_t sz = topic_list->cnt;
+  tmq->clientTopics = taosArrayInit(sz, sizeof(void*));
+  for (int i = 0; i < sz; i++) {
+    char* topicName = strdup(topic_list->elems[i]);
+    taosArrayPush(tmq->clientTopics, &topicName); 
+  }
+  SCMSubscribeReq req;
+  req.topicNum = taosArrayGetSize(tmq->clientTopics);
+  req.consumerId = tmq->consumerId;
+  req.consumerGroup = strdup(tmq->groupId);
+  req.topicNames = tmq->clientTopics;
+
+  int tlen = tSerializeSCMSubscribeReq(NULL, &req);
+  void* buf = malloc(tlen);
+  if(buf == NULL) {
+    goto _return;
+  }
+
+  void* abuf = buf;
+  tSerializeSCMSubscribeReq(&abuf, &req);
+  /*printf("formatted: %s\n", dagStr);*/
+
+  pRequest = createRequest(tmq->pTscObj, NULL, NULL, TSDB_SQL_SELECT);
+  if (pRequest == NULL) {
+    tscError("failed to malloc sqlObj");
+  }
+
+  pRequest->body.requestMsg = (SDataBuf){ .pData = buf, .len = tlen };
+  pRequest->type = TDMT_MND_CREATE_TOPIC;
+
+  SMsgSendInfo* body = buildMsgInfoImpl(pRequest);
+  SEpSet epSet = getEpSet_s(&tmq->pTscObj->pAppInfo->mgmtEp);
+
+  int64_t transporterId = 0;
+  asyncSendMsgToServer(tmq->pTscObj->pAppInfo->pTransporter, &epSet, &transporterId, body);
+
+  tsem_wait(&pRequest->body.rspSem);
+
+_return:
+  if (body != NULL) {
+    destroySendMsgInfo(body);
+  }
+
+  if (pRequest != NULL && terrno != TSDB_CODE_SUCCESS) {
+    pRequest->code = terrno;
+  }
+
+  return pRequest;
+}
 
 void tmq_conf_set_offset_commit_cb(tmq_conf_t* conf, tmq_commit_cb* cb) {
   conf->commit_cb = cb;
@@ -327,10 +445,10 @@ SArray* tmqGetConnInfo(SClientHbKey connKey, void* param) {
   int sz = taosArrayGetSize(clientTopics);
   for (int i = 0; i < sz; i++) {
     SMqClientTopic* pCTopic = taosArrayGet(clientTopics, i);
-    if (pCTopic->vgId == -1) {
-      pMqHb->status = 1;
-      break;
-    }
+    /*if (pCTopic->vgId == -1) {*/
+      /*pMqHb->status = 1;*/
+      /*break;*/
+    /*}*/
   }
   kv.value = pMqHb;
   kv.valueLen = sizeof(SMqHbMsg);
@@ -451,22 +569,63 @@ _return:
   return pRequest;
 }
 
-typedef struct tmq_message_t {
-  int32_t  numOfRows;
-  char*    topicName;
-  TAOS_ROW row[];
-} tmq_message_t;
+/*typedef SMqConsumeRsp tmq_message_t;*/
 
-tmq_message_t* tmq_consume_poll(tmq_t* mq, int64_t blocking_time) {
-  return NULL;
+struct tmq_message_t {
+  SMqConsumeRsp rsp;
+};
+
+tmq_message_t* tmq_consume_poll(tmq_t* tmq, int64_t blocking_time) {
+  if (tmq->clientTopics == NULL || taosArrayGetSize(tmq->clientTopics) == 0) {
+    return NULL;
+  }
+  SRequestObj *pRequest = NULL;
+  SMqConsumeReq req = {0};
+  req.reqType = 1;
+  req.blockingTime = blocking_time;
+  req.consumerId = tmq->consumerId;
+  strcpy(req.cgroup, tmq->groupId);
+
+  SMqClientTopic* pTopic = taosArrayGet(tmq->clientTopics, tmq->nextTopicIdx);
+  tmq->nextTopicIdx = (tmq->nextTopicIdx + 1) % taosArrayGetSize(tmq->clientTopics);
+  strcpy(req.topic, pTopic->topicName);
+  int32_t nextVgIdx = pTopic->nextVgIdx;
+  pTopic->nextVgIdx = (nextVgIdx + 1) % taosArrayGetSize(pTopic->vgs);
+  SMqClientVg* pVg = taosArrayGet(pTopic->vgs, nextVgIdx);
+  req.offset = pVg->currentOffset;
+
+  pRequest->body.requestMsg = (SDataBuf){ .pData = &req, .len = sizeof(SMqConsumeReq) };
+  pRequest->type = TDMT_VND_CONSUME;
+
+  SMsgSendInfo* body = buildMsgInfoImpl(pRequest);
+
+  int64_t transporterId = 0;
+  asyncSendMsgToServer(tmq->pTscObj->pAppInfo->pTransporter, &pVg->epSet, &transporterId, body);
+
+  tsem_wait(&pRequest->body.rspSem);
+
+  return (tmq_message_t*)pRequest->body.resInfo.pData;
+
+  /*tsem_wait(&pRequest->body.rspSem);*/
+
+  /*if (body != NULL) {*/
+    /*destroySendMsgInfo(body);*/
+  /*}*/
+
+  /*if (pRequest != NULL && terrno != TSDB_CODE_SUCCESS) {*/
+    /*pRequest->code = terrno;*/
+  /*}*/
+
+  /*return pRequest;*/
 }
 
-tmq_resp_err_t* tmq_commit(tmq_t* mq, void* callback, int32_t async) {
+tmq_resp_err_t* tmq_commit(tmq_t* tmq, tmq_topic_vgroup_list_t* tmq_topic_vgroup_list, int32_t async) {
+  SMqConsumeReq req = {0};
   return NULL;
 }
 
-void tmq_message_destroy(tmq_message_t* mq_message) {
-
+void tmq_message_destroy(tmq_message_t* tmq_message) {
+  if (tmq_message == NULL) return;
 }
 
 
diff --git a/source/client/src/clientMsgHandler.c b/source/client/src/clientMsgHandler.c
index 81ea18fe08afa1ab70af3f06b994f167a9423dc4..ec088eb0735824f3348287ec54fd476f00dc7adb 100644
--- a/source/client/src/clientMsgHandler.c
+++ b/source/client/src/clientMsgHandler.c
@@ -72,7 +72,7 @@ int processConnectRsp(void* param, const SDataBuf* pMsg, int32_t code) {
   atomic_add_fetch_64(&pTscObj->pAppInfo->numOfConns, 1);
 
   SClientHbKey connKey = {.connId = pConnect->connId, .hbType = HEARTBEAT_TYPE_QUERY};
-  /*hbRegisterConn(pTscObj->pAppInfo->pAppHbMgr, connKey, NULL);*/
+  hbRegisterConn(pTscObj->pAppInfo->pAppHbMgr, connKey, NULL);
 
   //  pRequest->body.resInfo.pRspMsg = pMsg->pData;
   tscDebug("0x%" PRIx64 " clusterId:%" PRId64 ", totalConn:%" PRId64, pRequest->requestId, pConnect->clusterId,
diff --git a/source/client/test/clientTests.cpp b/source/client/test/clientTests.cpp
index ee23567705c8c2799309e5ef04aec0dec5390e06..a2a26cf6dce54b7847a22af32797ddcaa6e455a9 100644
--- a/source/client/test/clientTests.cpp
+++ b/source/client/test/clientTests.cpp
@@ -526,29 +526,54 @@ TEST(testCase, show_table_Test) {
 //  taosHashCleanup(phash);
 //}
 //
-//TEST(testCase, create_topic_Test) {
-//  TAOS* pConn = taos_connect("localhost", "root", "taosdata", NULL, 0);
-//  assert(pConn != NULL);
-//
-//  TAOS_RES* pRes = taos_query(pConn, "use abc1");
-//  if (taos_errno(pRes) != 0) {
-//    printf("error in use db, reason:%s\n", taos_errstr(pRes));
-//  }
-//  taos_free_result(pRes);
-//
-//  TAOS_FIELD* pFields = taos_fetch_fields(pRes);
-//  ASSERT_TRUE(pFields == nullptr);
-//
-//  int32_t numOfFields = taos_num_fields(pRes);
-//  ASSERT_EQ(numOfFields, 0);
-//
-//  taos_free_result(pRes);
-//
-//  char* sql = "select * from tu";
-//  pRes = taos_create_topic(pConn, "test_topic_1", sql, strlen(sql));
-//  taos_free_result(pRes);
-//  taos_close(pConn);
-//}
+TEST(testCase, create_topic_Test) {
+  TAOS* pConn = taos_connect("localhost", "root", "taosdata", NULL, 0);
+  assert(pConn != NULL);
+
+  TAOS_RES* pRes = taos_query(pConn, "use abc1");
+  if (taos_errno(pRes) != 0) {
+    printf("error in use db, reason:%s\n", taos_errstr(pRes));
+  }
+  taos_free_result(pRes);
+
+  TAOS_FIELD* pFields = taos_fetch_fields(pRes);
+  ASSERT_TRUE(pFields == nullptr);
+
+  int32_t numOfFields = taos_num_fields(pRes);
+  ASSERT_EQ(numOfFields, 0);
+
+  taos_free_result(pRes);
+
+  char* sql = "select * from tu";
+  pRes = taos_create_topic(pConn, "test_topic_1", sql, strlen(sql));
+  taos_free_result(pRes);
+  taos_close(pConn);
+}
+
+TEST(testCase, tmq_subscribe_Test) {
+  TAOS* pConn = taos_connect("localhost", "root", "taosdata", NULL, 0);
+  assert(pConn != NULL);
+
+  tmq_conf_t* conf = tmq_conf_new();
+  tmq_conf_set(conf, "group.id", "tg1");
+  tmq_t* tmq = taos_consumer_new(pConn, conf, NULL, 0);
+  
+  tmq_list_t* topic_list = tmq_list_new();
+  tmq_list_append(topic_list, "test_topic_1");
+  tmq_subscribe(tmq, topic_list);
+
+  while (1) {
+    tmq_message_t* msg = tmq_consume_poll(tmq, 0);
+    printf("get msg\n");
+    if (msg == NULL) break;
+  }
+}
+
+TEST(testCase, tmq_consume_Test) {
+}
+
+TEST(testCase, tmq_commit_TEST) {
+}
 
 //TEST(testCase, insert_test) {
 //  TAOS* pConn = taos_connect("localhost", "root", "taosdata", NULL, 0);
@@ -681,4 +706,4 @@ TEST(testCase, projection_query_tables) {
 //  taos_close(pConn);
 //}
 
-#pragma GCC diagnostic pop
\ No newline at end of file
+#pragma GCC diagnostic pop
diff --git a/source/dnode/mnode/impl/inc/mndDef.h b/source/dnode/mnode/impl/inc/mndDef.h
index 1507e2a30d472cd5a9bed64ec6433e24fdf4091c..78f371133cceeca9963e4b7f755ccb1e61a8a99d 100644
--- a/source/dnode/mnode/impl/inc/mndDef.h
+++ b/source/dnode/mnode/impl/inc/mndDef.h
@@ -19,14 +19,14 @@
 #include "os.h"
 
 #include "cJSON.h"
+#include "scheduler.h"
 #include "sync.h"
-#include "tmsg.h"
 #include "thash.h"
 #include "tlist.h"
 #include "tlog.h"
+#include "tmsg.h"
 #include "trpc.h"
 #include "ttimer.h"
-#include "scheduler.h"
 
 #include "mnode.h"
 
@@ -37,12 +37,42 @@ extern "C" {
 extern int32_t mDebugFlag;
 
 // mnode log function
-#define mFatal(...) { if (mDebugFlag & DEBUG_FATAL) { taosPrintLog("MND FATAL ", 255, __VA_ARGS__); }}
-#define mError(...) { if (mDebugFlag & DEBUG_ERROR) { taosPrintLog("MND ERROR ", 255, __VA_ARGS__); }}
-#define mWarn(...)  { if (mDebugFlag & DEBUG_WARN)  { taosPrintLog("MND WARN ", 255, __VA_ARGS__); }}
-#define mInfo(...)  { if (mDebugFlag & DEBUG_INFO)  { taosPrintLog("MND ", 255, __VA_ARGS__); }}
-#define mDebug(...) { if (mDebugFlag & DEBUG_DEBUG) { taosPrintLog("MND ", mDebugFlag, __VA_ARGS__); }}
-#define mTrace(...) { if (mDebugFlag & DEBUG_TRACE) { taosPrintLog("MND ", mDebugFlag, __VA_ARGS__); }}
+#define mFatal(...)                                 \
+  {                                                 \
+    if (mDebugFlag & DEBUG_FATAL) {                 \
+      taosPrintLog("MND FATAL ", 255, __VA_ARGS__); \
+    }                                               \
+  }
+#define mError(...)                                 \
+  {                                                 \
+    if (mDebugFlag & DEBUG_ERROR) {                 \
+      taosPrintLog("MND ERROR ", 255, __VA_ARGS__); \
+    }                                               \
+  }
+#define mWarn(...)                                 \
+  {                                                \
+    if (mDebugFlag & DEBUG_WARN) {                 \
+      taosPrintLog("MND WARN ", 255, __VA_ARGS__); \
+    }                                              \
+  }
+#define mInfo(...)                            \
+  {                                           \
+    if (mDebugFlag & DEBUG_INFO) {            \
+      taosPrintLog("MND ", 255, __VA_ARGS__); \
+    }                                         \
+  }
+#define mDebug(...)                                  \
+  {                                                  \
+    if (mDebugFlag & DEBUG_DEBUG) {                  \
+      taosPrintLog("MND ", mDebugFlag, __VA_ARGS__); \
+    }                                                \
+  }
+#define mTrace(...)                                  \
+  {                                                  \
+    if (mDebugFlag & DEBUG_TRACE) {                  \
+      taosPrintLog("MND ", mDebugFlag, __VA_ARGS__); \
+    }                                                \
+  }
 
 typedef enum {
   MND_AUTH_ACCT_START = 0,
@@ -96,13 +126,13 @@ typedef struct {
   ETrnPolicy policy;
   int32_t    code;
   int32_t    failedTimes;
-  void      *rpcHandle;
-  void      *rpcAHandle;
-  SArray    *redoLogs;
-  SArray    *undoLogs;
-  SArray    *commitLogs;
-  SArray    *redoActions;
-  SArray    *undoActions;
+  void*      rpcHandle;
+  void*      rpcAHandle;
+  SArray*    redoLogs;
+  SArray*    undoLogs;
+  SArray*    commitLogs;
+  SArray*    redoActions;
+  SArray*    undoActions;
 } STrans;
 
 typedef struct {
@@ -135,28 +165,28 @@ typedef struct {
   ESyncState role;
   int32_t    roleTerm;
   int64_t    roleTime;
-  SDnodeObj *pDnode;
+  SDnodeObj* pDnode;
 } SMnodeObj;
 
 typedef struct {
   int32_t    id;
   int64_t    createdTime;
   int64_t    updateTime;
-  SDnodeObj *pDnode;
+  SDnodeObj* pDnode;
 } SQnodeObj;
 
 typedef struct {
   int32_t    id;
   int64_t    createdTime;
   int64_t    updateTime;
-  SDnodeObj *pDnode;
+  SDnodeObj* pDnode;
 } SSnodeObj;
 
 typedef struct {
   int32_t    id;
   int64_t    createdTime;
   int64_t    updateTime;
-  SDnodeObj *pDnode;
+  SDnodeObj* pDnode;
 } SBnodeObj;
 
 typedef struct {
@@ -201,7 +231,7 @@ typedef struct {
   int64_t   updateTime;
   int8_t    superUser;
   int32_t   acctId;
-  SHashObj *prohibitDbHash;
+  SHashObj* prohibitDbHash;
 } SUserObj;
 
 typedef struct {
@@ -226,15 +256,15 @@ typedef struct {
 } SDbCfg;
 
 typedef struct {
-  char    name[TSDB_DB_FNAME_LEN];
-  char    acct[TSDB_USER_LEN];
-  int64_t createdTime;
-  int64_t updateTime;
+  char     name[TSDB_DB_FNAME_LEN];
+  char     acct[TSDB_USER_LEN];
+  int64_t  createdTime;
+  int64_t  updateTime;
   uint64_t uid;
-  int32_t cfgVersion;
-  int32_t vgVersion;
-  int8_t  hashMethod;  // default is 1
-  SDbCfg  cfg;
+  int32_t  cfgVersion;
+  int32_t  vgVersion;
+  int8_t   hashMethod;  // default is 1
+  SDbCfg   cfg;
 } SDbObj;
 
 typedef struct {
@@ -272,7 +302,7 @@ typedef struct {
   int32_t  numOfColumns;
   int32_t  numOfTags;
   SRWLatch lock;
-  SSchema *pSchema;
+  SSchema* pSchema;
 } SStbObj;
 
 typedef struct {
@@ -287,8 +317,8 @@ typedef struct {
   int64_t sigature;
   int32_t commentSize;
   int32_t codeSize;
-  char   *pComment;
-  char   *pCode;
+  char*   pComment;
+  char*   pCode;
   char    pData[];
 } SFuncObj;
 
@@ -301,8 +331,8 @@ typedef struct {
   int32_t numOfRows;
   int32_t numOfReads;
   int32_t payloadLen;
-  void   *pIter;
-  SMnode *pMnode;
+  void*   pIter;
+  SMnode* pMnode;
   char    db[TSDB_DB_FNAME_LEN];
   int16_t offset[TSDB_MAX_COLUMNS];
   int32_t bytes[TSDB_MAX_COLUMNS];
@@ -327,9 +357,10 @@ typedef struct SMqTopicConsumer {
 #endif
 
 typedef struct SMqConsumerEp {
-  int32_t      vgId;      // -1 for unassigned
+  int32_t      vgId;  // -1 for unassigned
+  int32_t      status;
   SEpSet       epSet;
-  int64_t      consumerId; // -1 for unassigned
+  int64_t      consumerId;  // -1 for unassigned
   int64_t      lastConsumerHbTs;
   int64_t      lastVgHbTs;
   int32_t      execLen;
@@ -339,6 +370,7 @@ typedef struct SMqConsumerEp {
 static FORCE_INLINE int32_t tEncodeSMqConsumerEp(void** buf, SMqConsumerEp* pConsumerEp) {
   int32_t tlen = 0;
   tlen += taosEncodeFixedI32(buf, pConsumerEp->vgId);
+  tlen += taosEncodeFixedI32(buf, pConsumerEp->status);
   tlen += taosEncodeSEpSet(buf, &pConsumerEp->epSet);
   tlen += taosEncodeFixedI64(buf, pConsumerEp->consumerId);
   tlen += tEncodeSSubQueryMsg(buf, &pConsumerEp->qExec);
@@ -347,6 +379,7 @@ static FORCE_INLINE int32_t tEncodeSMqConsumerEp(void** buf, SMqConsumerEp* pCon
 
 static FORCE_INLINE void* tDecodeSMqConsumerEp(void** buf, SMqConsumerEp* pConsumerEp) {
   buf = taosDecodeFixedI32(buf, &pConsumerEp->vgId);
+  buf = taosDecodeFixedI32(buf, &pConsumerEp->status);
   buf = taosDecodeSEpSet(buf, &pConsumerEp->epSet);
   buf = taosDecodeFixedI64(buf, &pConsumerEp->consumerId);
   buf = tDecodeSSubQueryMsg(buf, &pConsumerEp->qExec);
@@ -354,16 +387,17 @@ static FORCE_INLINE void* tDecodeSMqConsumerEp(void** buf, SMqConsumerEp* pConsu
   return buf;
 }
 
-//unit for rebalance
+// unit for rebalance
 typedef struct SMqSubscribeObj {
   char    key[TSDB_SUBSCRIBE_KEY_LEN];
   int32_t epoch;
-  //TODO: replace with priority queue
+  // TODO: replace with priority queue
   int32_t nextConsumerIdx;
-  SArray* availConsumer;        // SArray<int64_t> (consumerId)
-  SArray* assigned;             // SArray<SMqConsumerEp>
-  SArray* unassignedConsumer;   // SArray<SMqConsumerEp>
-  SArray* unassignedVg;         // SArray<SMqConsumerEp>
+  SArray* availConsumer;  // SArray<int64_t> (consumerId)
+  SArray* assigned;       // SArray<SMqConsumerEp>
+  SArray* idleConsumer;   // SArray<SMqConsumerEp>
+  SArray* lostConsumer;   // SArray<SMqConsumerEp>
+  SArray* unassignedVg;   // SArray<SMqConsumerEp>
 } SMqSubscribeObj;
 
 static FORCE_INLINE SMqSubscribeObj* tNewSubscribeObj() {
@@ -384,17 +418,17 @@ static FORCE_INLINE SMqSubscribeObj* tNewSubscribeObj() {
     free(pSub);
     return NULL;
   }
-  pSub->unassignedConsumer = taosArrayInit(0, sizeof(SMqConsumerEp));
+  pSub->idleConsumer = taosArrayInit(0, sizeof(SMqConsumerEp));
   if (pSub->assigned == NULL) {
     taosArrayDestroy(pSub->availConsumer);
-    taosArrayDestroy(pSub->unassignedConsumer);
+    taosArrayDestroy(pSub->idleConsumer);
     free(pSub);
     return NULL;
   }
   pSub->unassignedVg = taosArrayInit(0, sizeof(SMqConsumerEp));
   if (pSub->assigned == NULL) {
     taosArrayDestroy(pSub->availConsumer);
-    taosArrayDestroy(pSub->unassignedConsumer);
+    taosArrayDestroy(pSub->idleConsumer);
     taosArrayDestroy(pSub->unassignedVg);
     free(pSub);
     return NULL;
@@ -422,10 +456,10 @@ static FORCE_INLINE int32_t tEncodeSubscribeObj(void** buf, const SMqSubscribeOb
     tlen += tEncodeSMqConsumerEp(buf, pCEp);
   }
 
-  sz = taosArrayGetSize(pSub->unassignedConsumer);
+  sz = taosArrayGetSize(pSub->idleConsumer);
   tlen += taosEncodeFixedI32(buf, sz);
   for (int32_t i = 0; i < sz; i++) {
-    SMqConsumerEp* pCEp = taosArrayGet(pSub->unassignedConsumer, i);
+    SMqConsumerEp* pCEp = taosArrayGet(pSub->idleConsumer, i);
     tlen += tEncodeSMqConsumerEp(buf, pCEp);
   }
 
@@ -457,22 +491,22 @@ static FORCE_INLINE void* tDecodeSubscribeObj(void* buf, SMqSubscribeObj* pSub)
   }
 
   buf = taosDecodeFixedI32(buf, &sz);
-  pSub->unassignedConsumer = taosArrayInit(sz, sizeof(SMqConsumerEp));
-  if (pSub->unassignedConsumer == NULL) {
+  pSub->idleConsumer = taosArrayInit(sz, sizeof(SMqConsumerEp));
+  if (pSub->idleConsumer == NULL) {
     taosArrayDestroy(pSub->assigned);
     return NULL;
   }
   for (int32_t i = 0; i < sz; i++) {
     SMqConsumerEp cEp;
     buf = tDecodeSMqConsumerEp(buf, &cEp);
-    taosArrayPush(pSub->unassignedConsumer, &cEp);
+    taosArrayPush(pSub->idleConsumer, &cEp);
   }
 
   buf = taosDecodeFixedI32(buf, &sz);
   pSub->unassignedVg = taosArrayInit(sz, sizeof(SMqConsumerEp));
   if (pSub->unassignedVg == NULL) {
     taosArrayDestroy(pSub->assigned);
-    taosArrayDestroy(pSub->unassignedConsumer);
+    taosArrayDestroy(pSub->idleConsumer);
     return NULL;
   }
   for (int32_t i = 0; i < sz; i++) {
@@ -487,38 +521,37 @@ static FORCE_INLINE void* tDecodeSubscribeObj(void* buf, SMqSubscribeObj* pSub)
 typedef struct SMqCGroup {
   char    name[TSDB_CONSUMER_GROUP_LEN];
   int32_t status;       // 0 - uninitialized, 1 - wait rebalance, 2- normal
-  SList  *consumerIds;  // SList<int64_t>
-  SList  *idleVGroups;  // SList<int32_t>
+  SList*  consumerIds;  // SList<int64_t>
+  SList*  idleVGroups;  // SList<int32_t>
 } SMqCGroup;
 
 typedef struct SMqTopicObj {
-  char      name[TSDB_TOPIC_FNAME_LEN];
-  char      db[TSDB_DB_FNAME_LEN];
-  int64_t   createTime;
-  int64_t   updateTime;
-  uint64_t  uid;
-  uint64_t  dbUid;
-  int32_t   version;
-  SRWLatch  lock;
-  int32_t   sqlLen;
-  char     *sql;
-  char     *logicalPlan;
-  char     *physicalPlan;
-  //SHashObj *cgroups;  // SHashObj<SMqCGroup>
-  //SHashObj *consumers;  // SHashObj<SMqConsumerObj>
+  char     name[TSDB_TOPIC_FNAME_LEN];
+  char     db[TSDB_DB_FNAME_LEN];
+  int64_t  createTime;
+  int64_t  updateTime;
+  uint64_t uid;
+  uint64_t dbUid;
+  int32_t  version;
+  SRWLatch lock;
+  int32_t  sqlLen;
+  char*    sql;
+  char*    logicalPlan;
+  char*    physicalPlan;
+  // SHashObj *cgroups;  // SHashObj<SMqCGroup>
+  // SHashObj *consumers;  // SHashObj<SMqConsumerObj>
 } SMqTopicObj;
 
 // TODO: add cache and change name to id
 typedef struct SMqConsumerTopic {
   char    name[TSDB_TOPIC_FNAME_LEN];
   int32_t epoch;
-  //TODO: replace with something with ep
-  //SList   *vgroups;  // SList<int32_t>
-  //vg assigned to the consumer on the topic
-  SArray  *pVgInfo;  // SArray<int32_t>
+  // vg assigned to the consumer on the topic
+  SArray* pVgInfo;  // SArray<int32_t>
 } SMqConsumerTopic;
 
-static FORCE_INLINE SMqConsumerTopic* tNewConsumerTopic(int64_t consumerId, SMqTopicObj* pTopic, SMqSubscribeObj* pSub) {
+static FORCE_INLINE SMqConsumerTopic* tNewConsumerTopic(int64_t consumerId, SMqTopicObj* pTopic,
+                                                        SMqSubscribeObj* pSub) {
   SMqConsumerTopic* pCTopic = malloc(sizeof(SMqConsumerTopic));
   if (pCTopic == NULL) {
     terrno = TSDB_CODE_OUT_OF_MEMORY;
@@ -567,10 +600,11 @@ static FORCE_INLINE void* tDecodeSMqConsumerTopic(void* buf, SMqConsumerTopic* p
 
 typedef struct SMqConsumerObj {
   int64_t  consumerId;
+  int64_t  connId;
   SRWLatch lock;
   char     cgroup[TSDB_CONSUMER_GROUP_LEN];
-  SArray  *topics;  // SArray<SMqConsumerTopic>
-  //SHashObj *topicHash; //SHashObj<SMqTopicObj>
+  SArray*  topics;  // SArray<SMqConsumerTopic>
+  // SHashObj *topicHash; //SHashObj<SMqTopicObj>
 } SMqConsumerObj;
 
 static FORCE_INLINE int32_t tEncodeSMqConsumerObj(void** buf, const SMqConsumerObj* pConsumer) {
@@ -602,12 +636,12 @@ static FORCE_INLINE void* tDecodeSMqConsumerObj(void* buf, SMqConsumerObj* pCons
 
 typedef struct SMqSubConsumerObj {
   int64_t consumerUid;  // if -1, unassigned
-  SList  *vgId;         // SList<int32_t>
+  SList*  vgId;         // SList<int32_t>
 } SMqSubConsumerObj;
 
 typedef struct SMqSubCGroupObj {
   char   name[TSDB_CONSUMER_GROUP_LEN];
-  SList *consumers;  // SList<SMqConsumerObj>
+  SList* consumers;  // SList<SMqConsumerObj>
 } SMqSubCGroupObj;
 
 typedef struct SMqSubTopicObj {
@@ -620,30 +654,30 @@ typedef struct SMqSubTopicObj {
   int32_t  version;
   SRWLatch lock;
   int32_t  sqlLen;
-  char    *sql;
-  char    *logicalPlan;
-  char    *physicalPlan;
-  SList   *cgroups;  // SList<SMqSubCGroupObj>
+  char*    sql;
+  char*    logicalPlan;
+  char*    physicalPlan;
+  SList*   cgroups;  // SList<SMqSubCGroupObj>
 } SMqSubTopicObj;
 
 typedef struct SMqConsumerSubObj {
   int64_t topicUid;
-  SList  *vgIds;  // SList<int64_t>
+  SList*  vgIds;  // SList<int64_t>
 } SMqConsumerSubObj;
 
 typedef struct SMqConsumerHbObj {
   int64_t consumerId;
-  SList  *consumerSubs;  // SList<SMqConsumerSubObj>
+  SList*  consumerSubs;  // SList<SMqConsumerSubObj>
 } SMqConsumerHbObj;
 
 typedef struct SMqVGroupSubObj {
   int64_t topicUid;
-  SList  *consumerIds;  // SList<int64_t>
+  SList*  consumerIds;  // SList<int64_t>
 } SMqVGroupSubObj;
 
 typedef struct SMqVGroupHbObj {
   int64_t vgId;
-  SList  *vgSubs;  // SList<SMqVGroupSubObj>
+  SList*  vgSubs;  // SList<SMqVGroupSubObj>
 } SMqVGroupHbObj;
 
 #if 0
@@ -663,11 +697,11 @@ typedef struct SMnodeMsg {
   char    user[TSDB_USER_LEN];
   char    db[TSDB_DB_FNAME_LEN];
   int32_t acctId;
-  SMnode *pMnode;
+  SMnode* pMnode;
   int64_t createdTime;
   SRpcMsg rpcMsg;
   int32_t contLen;
-  void   *pCont;
+  void*   pCont;
 } SMnodeMsg;
 
 #ifdef __cplusplus
diff --git a/source/dnode/mnode/impl/src/mndSubscribe.c b/source/dnode/mnode/impl/src/mndSubscribe.c
index 817ca4f4bede60d3ea76bd4edd73e4bfaf8e6a91..9a573cbe2c44ca9d43fb30ef8f324a056906445f 100644
--- a/source/dnode/mnode/impl/src/mndSubscribe.c
+++ b/source/dnode/mnode/impl/src/mndSubscribe.c
@@ -98,7 +98,8 @@ static int32_t mndProcessMqTimerMsg(SMnodeMsg *pMsg) {
         // build msg
         SMqSetCVgReq req = {
             .vgId = pCEp->vgId,
-            .consumerId = consumerId,
+            .oldConsumerId = -1,
+            .newConsumerId = consumerId,
         };
         strcpy(req.cgroup, cgroup);
         strcpy(req.topicName, topic);
@@ -152,6 +153,7 @@ static int mndInitUnassignedVg(SMnode *pMnode, SMqTopicObj *pTopic, SArray *unas
   //convert dag to msg
   for (int32_t i = 0; i < sz; i++) {
     SMqConsumerEp CEp;
+    CEp.status = 0;
     CEp.lastConsumerHbTs = CEp.lastVgHbTs = -1;
     STaskInfo* pTaskInfo = taosArrayGet(pArray, i);
     tConvertQueryAddrToEpSet(&CEp.epSet, &pTaskInfo->addr);
@@ -171,7 +173,8 @@ static int mndBuildMqSetConsumerVgReq(SMnode *pMnode, STrans *pTrans, SMqConsume
     SVgObj      *pVgObj = mndAcquireVgroup(pMnode, vgId);
     SMqSetCVgReq req = {
         .vgId = vgId,
-        .consumerId = pConsumer->consumerId,
+        .oldConsumerId = -1,
+        .newConsumerId = pConsumer->consumerId,
     };
     strcpy(req.cgroup, pConsumer->cgroup);
     strcpy(req.topicName, pTopic->name);
@@ -451,12 +454,13 @@ static int32_t mndProcessSubscribeReq(SMnodeMsg *pMsg) {
 
       SMqTopicObj *pTopic = mndAcquireTopic(pMnode, newTopicName);
       if (pTopic == NULL) {
-        /*terrno = */
+        mError("topic being subscribed not exist: %s", newTopicName);
         continue;
       }
 
       SMqSubscribeObj *pSub = mndAcquireSubscribe(pMnode, consumerGroup, newTopicName);
       if (pSub == NULL) {
+        mDebug("create new subscription, group: %s, topic %s", consumerGroup, newTopicName);
         pSub = tNewSubscribeObj();
         if (pSub == NULL) {
           terrno = TSDB_CODE_OUT_OF_MEMORY;
@@ -464,14 +468,15 @@ static int32_t mndProcessSubscribeReq(SMnodeMsg *pMsg) {
         }
         // set unassigned vg
         mndInitUnassignedVg(pMnode, pTopic, pSub->unassignedVg);
+        //TODO: disable alter
       }
       taosArrayPush(pSub->availConsumer, &consumerId);
 
-      // TODO: no need
       SMqConsumerTopic *pConsumerTopic = tNewConsumerTopic(consumerId, pTopic, pSub);
       taosArrayPush(pConsumer->topics, pConsumerTopic);
 
       if (taosArrayGetSize(pConsumerTopic->pVgInfo) > 0) {
+        ASSERT(taosArrayGetSize(pConsumerTopic->pVgInfo) == 1);
         int32_t vgId = *(int32_t *)taosArrayGetLast(pConsumerTopic->pVgInfo);
         // send setmsg to vnode
         if (mndBuildMqSetConsumerVgReq(pMnode, pTrans, pConsumer, pConsumerTopic, pTopic) < 0) {
@@ -479,8 +484,7 @@ static int32_t mndProcessSubscribeReq(SMnodeMsg *pMsg) {
           return -1;
         }
       }
-      taosArrayDestroy(pConsumerTopic->pVgInfo);
-      free(pConsumerTopic);
+
       SSdbRaw *pRaw = mndSubActionEncode(pSub);
       /*sdbSetRawStatus(pRaw, SDB_STATUS_READY);*/
       mndTransAppendRedolog(pTrans, pRaw);
@@ -533,12 +537,12 @@ static int32_t mndProcessSubscribeReq(SMnodeMsg *pMsg) {
 
   if (mndTransPrepare(pMnode, pTrans) != 0) {
     mError("trans:%d, failed to prepare since %s", pTrans->id, terrstr());
+    if (newSub) taosArrayDestroy(newSub);
     mndTransDrop(pTrans);
     mndReleaseConsumer(pMnode, pConsumer);
     return -1;
   }
 
-  // TODO: free memory
   if (newSub) taosArrayDestroy(newSub);
   mndTransDrop(pTrans);
   mndReleaseConsumer(pMnode, pConsumer);
diff --git a/source/dnode/vnode/inc/tq.h b/source/dnode/vnode/inc/tq.h
index 9cc987d7316fcec2dc7334df09ef9ded0f93b23d..0f318dea0b409d79548dbca2ddb5721fccd4be4d 100644
--- a/source/dnode/vnode/inc/tq.h
+++ b/source/dnode/vnode/inc/tq.h
@@ -18,7 +18,6 @@
 
 #include "common.h"
 #include "executor.h"
-#include "vnode.h"
 #include "mallocator.h"
 #include "meta.h"
 #include "os.h"
@@ -29,6 +28,7 @@
 #include "trpc.h"
 #include "ttimer.h"
 #include "tutil.h"
+#include "vnode.h"
 #include "wal.h"
 
 #ifdef __cplusplus
@@ -149,10 +149,11 @@ typedef struct STqGroup {
 } STqGroup;
 
 typedef struct STqTaskItem {
-  int8_t      status;
-  int64_t     offset;
-  void*       dst;
-  qTaskInfo_t task;
+  int8_t        status;
+  int64_t       offset;
+  void*         dst;
+  qTaskInfo_t   task;
+  SSubQueryMsg* pQueryMsg;
 } STqTaskItem;
 
 // new version
@@ -164,7 +165,6 @@ typedef struct STqBuffer {
 
 typedef struct STqTopicHandle {
   char            topicName[TSDB_TOPIC_FNAME_LEN];
-  char            cgroup[TSDB_TOPIC_FNAME_LEN];
   char*           sql;
   char*           logicalPlan;
   char*           physicalPlan;
@@ -177,6 +177,7 @@ typedef struct STqTopicHandle {
 typedef struct STqConsumerHandle {
   int64_t consumerId;
   int64_t epoch;
+  char    cgroup[TSDB_TOPIC_FNAME_LEN];
   SArray* topics;  // SArray<STqClientTopic>
 } STqConsumerHandle;
 
@@ -318,7 +319,7 @@ int       tqSendLaunchQuery(STqMsgItem*, int64_t offset);
 #endif
 
 int32_t tqProcessConsumeReq(STQ* pTq, SRpcMsg* pMsg, SRpcMsg** ppRsp);
-int32_t tqProcessSetConnReq(STQ* pTq, SMqSetCVgReq* pReq);
+int32_t tqProcessSetConnReq(STQ* pTq, char* msg);
 
 #ifdef __cplusplus
 }
diff --git a/source/dnode/vnode/src/inc/tqInt.h b/source/dnode/vnode/src/inc/tqInt.h
index 2b4200fce563c638db7e1c8cb4f71bdaf18d99af..a9ba825a29af02a01d6c67d84a08c3814134a2d3 100644
--- a/source/dnode/vnode/src/inc/tqInt.h
+++ b/source/dnode/vnode/src/inc/tqInt.h
@@ -44,8 +44,10 @@ extern int32_t tqDebugFlag;
 // delete persistent storage for meta info
 // int tqDropTCGroup(STQ*, const char* topic, int cgId);
 
-int tqSerializeGroup(const STqGroup*, STqSerializedHead**);
-const void* tqDeserializeGroup(const STqSerializedHead* pHead, STqGroup** ppGroup);
+//int tqSerializeGroup(const STqGroup*, STqSerializedHead**);
+//const void* tqDeserializeGroup(const STqSerializedHead* pHead, STqGroup** ppGroup);
+int tqSerializeConsumer(const STqConsumerHandle*, STqSerializedHead**);
+const void* tqDeserializeConsumer(const STqSerializedHead* pHead, STqConsumerHandle**);
 static int FORCE_INLINE tqQueryExecuting(int32_t status) { return status; }
 #ifdef __cplusplus
 }
diff --git a/source/dnode/vnode/src/tq/tq.c b/source/dnode/vnode/src/tq/tq.c
index b18f50cd3f24606212e002ebca43bd35b20eb9e3..49bbb77797a4e01f81ee41356a77b1a3f3f39029 100644
--- a/source/dnode/vnode/src/tq/tq.c
+++ b/source/dnode/vnode/src/tq/tq.c
@@ -68,7 +68,7 @@ STQ* tqOpen(const char* path, SWal* pWal, SMeta* pMeta, STqCfg* tqConfig, SMemAl
     // TODO: error code of buffer pool
   }
 #endif
-  pTq->tqMeta = tqStoreOpen(path, (FTqSerialize)tqSerializeGroup, (FTqDeserialize)tqDeserializeGroup, free, 0);
+  pTq->tqMeta = tqStoreOpen(path, (FTqSerialize)tqSerializeConsumer, (FTqDeserialize)tqDeserializeConsumer, free, 0);
   if (pTq->tqMeta == NULL) {
     free(pTq);
 #if 0
@@ -478,6 +478,59 @@ int tqConsume(STQ* pTq, STqConsumeReq* pMsg) {
 }
 #endif
 
+int tqSerializeConsumer(const STqConsumerHandle* pConsumer, STqSerializedHead** ppHead) {
+  int32_t num = taosArrayGetSize(pConsumer->topics);
+  int32_t sz = sizeof(STqSerializedHead) + sizeof(int64_t) * 2 + TSDB_TOPIC_FNAME_LEN + num * (sizeof(int64_t) + TSDB_TOPIC_FNAME_LEN);
+  if (sz > (*ppHead)->ssize) {
+    void* tmpPtr = realloc(*ppHead, sz);
+    if (tmpPtr == NULL) {
+      free(*ppHead);
+      return -1;
+    }
+    *ppHead = tmpPtr;
+    (*ppHead)->ssize = sz;
+  }
+
+  void* ptr = (*ppHead)->content;
+  *(int64_t*)ptr = pConsumer->consumerId;
+  ptr = POINTER_SHIFT(ptr, sizeof(int64_t));
+  *(int64_t*)ptr = pConsumer->epoch;
+  ptr = POINTER_SHIFT(ptr, sizeof(int64_t));
+  memcpy(ptr, pConsumer->topics, TSDB_TOPIC_FNAME_LEN);
+  ptr = POINTER_SHIFT(ptr, TSDB_TOPIC_FNAME_LEN);
+  *(int32_t*)ptr = num;
+  ptr = POINTER_SHIFT(ptr, sizeof(int32_t));
+  for (int32_t i = 0; i < num; i++) {
+    STqTopicHandle* pTopic = taosArrayGet(pConsumer->topics, i);
+    memcpy(ptr, pTopic->topicName, TSDB_TOPIC_FNAME_LEN);
+    ptr = POINTER_SHIFT(ptr, TSDB_TOPIC_FNAME_LEN);
+    *(int64_t*)ptr = pTopic->committedOffset;
+    POINTER_SHIFT(ptr, sizeof(int64_t));
+  }
+  
+  return 0;
+}
+
+const void* tqDeserializeConsumer(const STqSerializedHead* pHead, STqConsumerHandle** ppConsumer) {
+  STqConsumerHandle* pConsumer = *ppConsumer;
+  const void* ptr = pHead->content;
+  pConsumer->consumerId = *(int64_t*)ptr;
+  ptr = POINTER_SHIFT(ptr, sizeof(int64_t));
+  pConsumer->epoch = *(int64_t*)ptr;
+  ptr = POINTER_SHIFT(ptr, sizeof(int64_t));
+  memcpy(pConsumer->cgroup, ptr, TSDB_TOPIC_FNAME_LEN);
+  ptr = POINTER_SHIFT(ptr, TSDB_TOPIC_FNAME_LEN);
+  int32_t sz = *(int32_t*)ptr;
+  ptr = POINTER_SHIFT(ptr, sizeof(int32_t));
+  pConsumer->topics = taosArrayInit(sz, sizeof(STqTopicHandle));
+  for (int32_t i = 0; i < sz; i++) {
+    /*STqTopicHandle* topicHandle = */
+    /*taosArrayPush(pConsumer->topics, );*/
+  }
+  return NULL;
+}
+
+#if 0
 int tqSerializeGroup(const STqGroup* pGroup, STqSerializedHead** ppHead) {
   // calculate size
   int sz = tqGroupSSize(pGroup) + sizeof(STqSerializedHead);
@@ -608,6 +661,7 @@ int tqItemSSize() {
   // mainly for executor
   return 0;
 }
+#endif
 
 int32_t tqProcessConsumeReq(STQ* pTq, SRpcMsg* pMsg, SRpcMsg** ppRsp) {
   SMqConsumeReq* pReq = pMsg->pCont;
@@ -625,7 +679,14 @@ int32_t tqProcessConsumeReq(STQ* pTq, SRpcMsg* pMsg, SRpcMsg** ppRsp) {
 
   for (int i = 0; i < sz; i++) {
     STqTopicHandle* pTopic = taosArrayGet(pConsumer->topics, i);
+    //TODO: support multiple topic in one req
+    if (strcmp(pTopic->topicName, pReq->topic) != 0) {
+      continue;
+    }
 
+  if (fetchOffset == -1) {
+    fetchOffset = pTopic->committedOffset + 1;
+  }
     int8_t pos;
     int8_t skip = 0;
     SWalHead* pHead;
@@ -670,6 +731,23 @@ int32_t tqProcessConsumeReq(STQ* pTq, SRpcMsg* pMsg, SRpcMsg** ppRsp) {
         break;
       }
       if (pDataBlock != NULL) {
+        SMqTbData tbData = {
+          .uid = pDataBlock->info.uid,
+          .numOfCols = pDataBlock->info.numOfCols,
+          .numOfRows = pDataBlock->info.rows,
+        };
+        for (int i = 0; i < pDataBlock->info.numOfCols; i++) {
+          SColumnInfoData* pColData = taosArrayGet(pDataBlock->pDataBlock, i);
+          int32_t sz = pColData->info.bytes * pDataBlock->info.rows;
+          SMqColData colData = {
+            .bytes = pColData->info.bytes,
+            .colId = pColData->info.colId,
+            .type = pColData->info.type,
+          };
+          memcpy(colData.data, pColData->pData, colData.bytes * pDataBlock->info.rows);
+          memcpy(&tbData.colData[i], &colData, sz);
+        }
+        /*pDataBlock->info.*/
         taosArrayPush(pRes, pDataBlock);
       } else {
         break;
@@ -692,29 +770,34 @@ int32_t tqProcessConsumeReq(STQ* pTq, SRpcMsg* pMsg, SRpcMsg** ppRsp) {
       pTopic->buffer.lastOffset = pReq->offset;
     }
     // put output into rsp
+    SMqConsumeRsp rsp = {
+      .consumerId = consumerId,
+      .numOfTopics = 1
+    };
   }
 
-  // launch query
-  // get result
   return 0;
 }
 
-int32_t tqProcessSetConnReq(STQ* pTq, SMqSetCVgReq* pReq) {
+int32_t tqProcessSetConnReq(STQ* pTq, char* msg) {
+  SMqSetCVgReq req;
+  tDecodeSMqSetCVgReq(msg, &req);
   STqConsumerHandle* pConsumer = calloc(sizeof(STqConsumerHandle), 1);
   if (pConsumer == NULL) {
     return -1;
   }
+  strcpy(pConsumer->cgroup, req.cgroup);
+  pConsumer->topics = taosArrayInit(0, sizeof(STqTopicHandle));
 
   STqTopicHandle* pTopic = calloc(sizeof(STqTopicHandle), 1);
   if (pTopic == NULL) {
     free(pConsumer);
     return -1;
   }
-  strcpy(pTopic->topicName, pReq->topicName);
-  strcpy(pTopic->cgroup, pReq->cgroup);
-  strcpy(pTopic->sql, pReq->sql);
-  strcpy(pTopic->logicalPlan, pReq->logicalPlan);
-  strcpy(pTopic->physicalPlan, pReq->physicalPlan);
+  strcpy(pTopic->topicName, req.topicName);
+  strcpy(pTopic->sql, req.sql);
+  strcpy(pTopic->logicalPlan, req.logicalPlan);
+  strcpy(pTopic->physicalPlan, req.physicalPlan);
 
   pTopic->buffer.firstOffset = -1;
   pTopic->buffer.lastOffset = -1;
@@ -724,9 +807,9 @@ int32_t tqProcessSetConnReq(STQ* pTq, SMqSetCVgReq* pReq) {
   for (int i = 0; i < TQ_BUFFER_SIZE; i++) {
     pTopic->buffer.output[i].status = 0;
     STqReadHandle* pReadHandle = tqInitSubmitMsgScanner(pTq->pMeta);
-    pTopic->buffer.output[i].task = qCreateStreamExecTaskInfo(&pReq->msg, pReadHandle);
+    pTopic->buffer.output[i].task = qCreateStreamExecTaskInfo(&req.msg, pReadHandle);
   }
-  // write mq meta
+  taosArrayPush(pConsumer->topics, pTopic);
   return 0;
 }
 
diff --git a/source/dnode/vnode/src/vnd/vnodeWrite.c b/source/dnode/vnode/src/vnd/vnodeWrite.c
index a6c3f25c6f0fcbe4653c9534a92601c246f2e42f..ccddfd56d8f89832790b364643981a62dba4cee7 100644
--- a/source/dnode/vnode/src/vnd/vnodeWrite.c
+++ b/source/dnode/vnode/src/vnd/vnodeWrite.c
@@ -112,9 +112,7 @@ int vnodeApplyWMsg(SVnode *pVnode, SRpcMsg *pMsg, SRpcMsg **pRsp) {
       }
       break;
     case TDMT_VND_MQ_SET_CONN: {
-      SMqSetCVgReq req;
-      tDecodeSMqSetCVgReq(ptr, &req);
-      if (tqProcessSetConnReq(pVnode->pTq, &req) < 0) {
+      if (tqProcessSetConnReq(pVnode->pTq, ptr) < 0) {
       }
     } break;
     default: