diff --git a/include/common/taosmsg.h b/include/common/taosmsg.h
index ccc8d3023ee1a2a83ddaf651bfd1575fa2140da6..2e0f59df04d54a65ffc8685c6e8efdd1ba90f0cb 100644
--- a/include/common/taosmsg.h
+++ b/include/common/taosmsg.h
@@ -75,9 +75,9 @@ TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_CREATE_FUNCTION, "create-function" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_ALTER_FUNCTION, "alter-function" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_DROP_FUNCTION, "drop-function" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_CREATE_STABLE, "create-stable" )
-TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_STABLE_VGROUP, "stable-vgroup" )
-TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_DROP_STABLE, "drop-stable" )	
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_ALTER_STABLE, "alter-stable" )
+TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_DROP_STABLE, "drop-stable" )	
+TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_STABLE_VGROUP, "stable-vgroup" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_KILL_QUERY, "kill-query" )	
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_KILL_CONN, "kill-conn" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_HEARTBEAT, "heartbeat" )
@@ -108,6 +108,7 @@ TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_AUTH_VNODE_IN, "auth-vnode" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_SYNC_VNODE_IN, "sync-vnode" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_COMPACT_VNODE_IN, "compact-vnode" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_CREATE_MNODE_IN, "create-mnode" )
+TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_ALTER_MNODE_IN, "alter-mnode" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_DROP_MNODE_IN, "drop-mnode" )
 TAOS_DEFINE_MESSAGE_TYPE( TSDB_MSG_TYPE_CONFIG_DNODE_IN, "config-dnode" )
 
@@ -700,32 +701,33 @@ typedef struct {
 } SStatusRsp;
 
 typedef struct {
-  uint16_t port;
-  char     fqdn[TSDB_FQDN_LEN];
-} SVnodeDesc;
-
-typedef struct {
-  char       db[TSDB_FULL_DB_NAME_LEN];
-  uint32_t   vgId;
-  int32_t    cacheBlockSize;
-  int32_t    totalBlocks;
-  int32_t    daysPerFile;
-  int32_t    daysToKeep0;
-  int32_t    daysToKeep1;
-  int32_t    daysToKeep2;
-  int32_t    minRowsPerFileBlock;
-  int32_t    maxRowsPerFileBlock;
-  int32_t    fsyncPeriod;
-  int8_t     reserved[16];
-  int8_t     precision;
-  int8_t     compression;
-  int8_t     cacheLastRow;
-  int8_t     update;
-  int8_t     walLevel;
-  int8_t     replica;
-  int8_t     quorum;
-  int8_t     selfIndex;
-  SVnodeDesc replicas[TSDB_MAX_REPLICA];
+  int32_t  id;
+  uint16_t port;                 // node sync Port
+  char     fqdn[TSDB_FQDN_LEN];  // node FQDN
+} SReplica;
+
+typedef struct {
+  char     db[TSDB_FULL_DB_NAME_LEN];
+  uint32_t vgId;
+  int32_t  cacheBlockSize;
+  int32_t  totalBlocks;
+  int32_t  daysPerFile;
+  int32_t  daysToKeep0;
+  int32_t  daysToKeep1;
+  int32_t  daysToKeep2;
+  int32_t  minRowsPerFileBlock;
+  int32_t  maxRowsPerFileBlock;
+  int32_t  fsyncPeriod;
+  int8_t   reserved[16];
+  int8_t   precision;
+  int8_t   compression;
+  int8_t   cacheLastRow;
+  int8_t   update;
+  int8_t   walLevel;
+  int8_t   quorum;
+  int8_t   replica;
+  int8_t   selfIndex;
+  SReplica replicas[TSDB_MAX_REPLICA];
 } SCreateVnodeMsg, SAlterVnodeMsg;
 
 typedef struct {
@@ -829,8 +831,11 @@ typedef struct {
 } SCreateDnodeMsg, SDropDnodeMsg;
 
 typedef struct {
-  int32_t   dnodeId;
-} SCreateMnodeMsg, SDropMnodeMsg;
+  int32_t    dnodeId;
+  int8_t     replica;
+  int8_t     reserved[3];
+  SReplica replicas[TSDB_MAX_REPLICA];
+} SCreateMnodeMsg, SAlterMnodeMsg, SDropMnodeMsg;
 
 typedef struct {
   int32_t dnodeId;
diff --git a/include/server/mnode/mnode.h b/include/server/mnode/mnode.h
index e0fcdec560df967c54106a99bd695d49f0f041b7..09dd4a3f2d89bdb9d9879adcd9f802ac3a7e67a2 100644
--- a/include/server/mnode/mnode.h
+++ b/include/server/mnode/mnode.h
@@ -20,6 +20,16 @@
 extern "C" {
 #endif
 
+typedef enum { MN_MSG_TYPE_WRITE = 1, MN_MSG_TYPE_APPLY, MN_MSG_TYPE_SYNC, MN_MSG_TYPE_READ } EMnMsgType;
+
+typedef struct SMnodeMsg SMnodeMsg;
+
+typedef struct {
+  int8_t   replica;
+  int8_t   selfIndex;
+  SReplica replicas[TSDB_MAX_REPLICA];
+} SMnodeCfg;
+
 typedef struct {
   int64_t numOfDnode;
   int64_t numOfMnode;
@@ -31,32 +41,33 @@ typedef struct {
   int64_t totalPoints;
   int64_t totalStorage;
   int64_t compStorage;
-} SMnodeStat;
+} SMnodeLoad;
 
 typedef struct {
+  int32_t dnodeId;
+  int64_t clusterId;
   void (*SendMsgToDnode)(struct SEpSet *epSet, struct SRpcMsg *rpcMsg);
   void (*SendMsgToMnode)(struct SRpcMsg *rpcMsg);
   void (*SendRedirectMsg)(struct SRpcMsg *rpcMsg, bool forShell);
-  void (*GetDnodeEp)(int32_t dnodeId, char *ep, char *fqdn, uint16_t *port);
-} SMnodeFp;
-
-typedef struct {
-  SMnodeFp fp;
-  int64_t  clusterId;
-  int32_t  dnodeId;
+  int32_t (*PutMsgIntoApplyQueue)(SMnodeMsg *pMsg);
 } SMnodePara;
 
 int32_t mnodeInit(SMnodePara para);
 void    mnodeCleanup();
-int32_t mnodeDeploy();
-void    mnodeUnDeploy();
-int32_t mnodeStart();
+
+int32_t mnodeDeploy(char *path, SMnodeCfg *pCfg);
+void    mnodeUnDeploy(char *path);
+int32_t mnodeStart(char *path, SMnodeCfg *pCfg);
+int32_t mnodeAlter(SMnodeCfg *pCfg);
 void    mnodeStop();
 
-int32_t mnodeGetStatistics(SMnodeStat *stat);
+int32_t mnodeGetLoad(SMnodeLoad *pLoad);
 int32_t mnodeRetriveAuth(char *user, char *spi, char *encrypt, char *secret, char *ckey);
 
-void mnodeProcessMsg(SRpcMsg *rpcMsg);
+SMnodeMsg *mnodeInitMsg(int32_t msgNum);
+int32_t    mnodeAppendMsg(SMnodeMsg *pMsg, SRpcMsg *pRpcMsg);
+void       mnodeCleanupMsg(SMnodeMsg *pMsg);
+void       mnodeProcessMsg(SMnodeMsg *pMsg, EMnMsgType msgType);
 
 #ifdef __cplusplus
 }
diff --git a/include/server/vnode/tq/tq.h b/include/server/vnode/tq/tq.h
index 4a9349105637eaa52dd41379557eb84a5f6120e7..3aeaf9acb6be607caea6bf60d8627875fa952df8 100644
--- a/include/server/vnode/tq/tq.h
+++ b/include/server/vnode/tq/tq.h
@@ -19,9 +19,6 @@
 #include "os.h"
 #include "tutil.h"
 
-#define TQ_ACTION_INSERT 0x7f7f7f7fULL
-#define TQ_ACTION_DELETE 0x80808080ULL
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/server/vnode/vnode.h b/include/server/vnode/vnode.h
index e570cf4261258aef2784ee3468d49ff792a5e020..352b98dec0796368f160c197930e59dfe6bbc462 100644
--- a/include/server/vnode/vnode.h
+++ b/include/server/vnode/vnode.h
@@ -27,24 +27,25 @@ extern "C" {
 typedef struct SVnode SVnode;
 
 typedef struct {
-  char       db[TSDB_FULL_DB_NAME_LEN];
-  int32_t    cacheBlockSize;  // MB
-  int32_t    totalBlocks;
-  int32_t    daysPerFile;
-  int32_t    daysToKeep0;
-  int32_t    daysToKeep1;
-  int32_t    daysToKeep2;
-  int32_t    minRowsPerFileBlock;
-  int32_t    maxRowsPerFileBlock;
-  int8_t     precision;  // time resolution
-  int8_t     compression;
-  int8_t     cacheLastRow;
-  int8_t     update;
-  int8_t     quorum;
-  int8_t     replica;
-  int8_t     walLevel;
-  int32_t    fsyncPeriod;  // millisecond
-  SVnodeDesc replicas[TSDB_MAX_REPLICA];
+  char     db[TSDB_FULL_DB_NAME_LEN];
+  int32_t  cacheBlockSize;  // MB
+  int32_t  totalBlocks;
+  int32_t  daysPerFile;
+  int32_t  daysToKeep0;
+  int32_t  daysToKeep1;
+  int32_t  daysToKeep2;
+  int32_t  minRowsPerFileBlock;
+  int32_t  maxRowsPerFileBlock;
+  int8_t   precision;  // time resolution
+  int8_t   compression;
+  int8_t   cacheLastRow;
+  int8_t   update;
+  int8_t   quorum;
+  int8_t   replica;
+  int8_t   selfIndex;
+  int8_t   walLevel;
+  int32_t  fsyncPeriod;  // millisecond
+  SReplica replicas[TSDB_MAX_REPLICA];
 } SVnodeCfg;
 
 typedef enum {
diff --git a/include/util/taoserror.h b/include/util/taoserror.h
index e2f9a580239645f899e4c49f1ea4a4c571a0a07b..6c46a4c89fffb10d3c7bafed62ed1b77a2ef181d 100644
--- a/include/util/taoserror.h
+++ b/include/util/taoserror.h
@@ -216,14 +216,18 @@ int32_t* taosGetErrno();
 // dnode
 #define TSDB_CODE_DND_MSG_NOT_PROCESSED         TAOS_DEF_ERROR_CODE(0, 0x0400)  //"Message not processed")
 #define TSDB_CODE_DND_OUT_OF_MEMORY             TAOS_DEF_ERROR_CODE(0, 0x0401)  //"Dnode out of memory")
-#define TSDB_CODE_DND_DNODE_ID_NOT_MATCHED      TAOS_DEF_ERROR_CODE(0, 0x0402)  //"Dnode Id not matched")
-#define TSDB_CODE_DND_MNODE_ALREADY_DROPPED     TAOS_DEF_ERROR_CODE(0, 0x0403)  //"Mnode already deployed")
-#define TSDB_CODE_DND_NO_WRITE_ACCESS           TAOS_DEF_ERROR_CODE(0, 0x0404)  //"No permission for disk files in dnode")
-#define TSDB_CODE_DND_INVALID_MSG_LEN           TAOS_DEF_ERROR_CODE(0, 0x0405)  //"Invalid message length")
-#define TSDB_CODE_DND_ACTION_IN_PROGRESS        TAOS_DEF_ERROR_CODE(0, 0x0406)  //"Action in progress")
-#define TSDB_CODE_DND_TOO_MANY_VNODES           TAOS_DEF_ERROR_CODE(0, 0x0407)  //"Too many vnode directories")
-#define TSDB_CODE_DND_EXITING                   TAOS_DEF_ERROR_CODE(0, 0x0408)  //"Dnode is exiting"
-#define TSDB_CODE_DND_PARSE_VNODE_FILE_ERROR    TAOS_DEF_ERROR_CODE(0, 0x0409)  //"Parse vnodes.json error")
+#define TSDB_CODE_DND_MNODE_ID_NOT_MATCH_DNODE  TAOS_DEF_ERROR_CODE(0, 0x0402)  //"Mnode Id not match Dnode")
+#define TSDB_CODE_DND_MNODE_ALREADY_DEPLOYED    TAOS_DEF_ERROR_CODE(0, 0x0403)  //"Mnode already deployed")
+#define TSDB_CODE_DND_MNODE_NOT_DEPLOYED        TAOS_DEF_ERROR_CODE(0, 0x0404)  //"Mnode not deployed")
+#define TSDB_CODE_DND_READ_MNODE_FILE_ERROR     TAOS_DEF_ERROR_CODE(0, 0x0405)  //"Read mnode.json error")
+#define TSDB_CODE_DND_WRITE_MNODE_FILE_ERROR    TAOS_DEF_ERROR_CODE(0, 0x0406)  //"Write mnode.json error")
+#define TSDB_CODE_DND_NO_WRITE_ACCESS           TAOS_DEF_ERROR_CODE(0, 0x0407)  //"No permission for disk files in dnode")
+#define TSDB_CODE_DND_INVALID_MSG_LEN           TAOS_DEF_ERROR_CODE(0, 0x0408)  //"Invalid message length")
+#define TSDB_CODE_DND_ACTION_IN_PROGRESS        TAOS_DEF_ERROR_CODE(0, 0x0409)  //"Action in progress")
+#define TSDB_CODE_DND_TOO_MANY_VNODES           TAOS_DEF_ERROR_CODE(0, 0x040A)  //"Too many vnode directories")
+#define TSDB_CODE_DND_EXITING                   TAOS_DEF_ERROR_CODE(0, 0x040B)  //"Dnode is exiting"
+#define TSDB_CODE_DND_PARSE_VNODE_FILE_ERROR    TAOS_DEF_ERROR_CODE(0, 0x040C)  //"Parse vnodes.json error")
+#define TSDB_CODE_DND_PARSE_DNODE_FILE_ERROR    TAOS_DEF_ERROR_CODE(0, 0x040D)  //"Parse dnodes.json error")
 
 // vnode
 #define TSDB_CODE_VND_ACTION_IN_PROGRESS        TAOS_DEF_ERROR_CODE(0, 0x0500)  //"Action in progress")
diff --git a/source/dnode/mgmt/inc/dnodeMnode.h b/source/dnode/mgmt/inc/dnodeMnode.h
index 28702dcb842d5c9373e109c31362983d848a6c0e..9f52e586fe13e294e93bb61c7ac5e6a513ffb6c7 100644
--- a/source/dnode/mgmt/inc/dnodeMnode.h
+++ b/source/dnode/mgmt/inc/dnodeMnode.h
@@ -23,9 +23,13 @@ extern "C" {
 
 int32_t dnodeInitMnode();
 void    dnodeCleanupMnode();
-void    dnodeProcessMnodeMsg(SRpcMsg *pMsg, SEpSet *pEpSet);
 int32_t dnodeGetUserAuthFromMnode(char *user, char *spi, char *encrypt, char *secret, char *ckey);
 
+void dnodeProcessMnodeMgmtMsg(SRpcMsg *pMsg, SEpSet *pEpSet);
+void dnodeProcessMnodeReadMsg(SRpcMsg *pMsg, SEpSet *pEpSet);
+void dnodeProcessMnodeWriteMsg(SRpcMsg *pMsg, SEpSet *pEpSet);
+void dnodeProcessMnodeSyncMsg(SRpcMsg *pMsg, SEpSet *pEpSet);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/dnode/mgmt/src/dnodeMnode.c b/source/dnode/mgmt/src/dnodeMnode.c
index 4414d57f3e6ec9ca7cb7ca5c4b0e2c9c3495c2c0..e5a758899eedc2ec68cd1c0ff5609d0d409f4042 100644
--- a/source/dnode/mgmt/src/dnodeMnode.c
+++ b/source/dnode/mgmt/src/dnodeMnode.c
@@ -15,73 +15,120 @@
 
 #define _DEFAULT_SOURCE
 #include "dnodeMnode.h"
+#include "cJSON.h"
 #include "dnodeDnode.h"
 #include "dnodeTransport.h"
-#include "cJSON.h"
 #include "mnode.h"
+#include "tlockfree.h"
+#include "tqueue.h"
+#include "tstep.h"
+#include "tworker.h"
 
 static struct {
-  int8_t          deployed;
-  int8_t          dropped;
-  char            file[PATH_MAX + 20];
-  pthread_mutex_t mutex;
+  int32_t     refCount;
+  int8_t      deployed;
+  int8_t      dropped;
+  SWorkerPool mgmtPool;
+  SWorkerPool readPool;
+  SWorkerPool writePool;
+  SWorkerPool syncPool;
+  taos_queue  pReadQ;
+  taos_queue  pWriteQ;
+  taos_queue  pApplyQ;
+  taos_queue  pSyncQ;
+  taos_queue  pMgmtQ;
+  SSteps     *pSteps;
+  SRWLatch    latch;
 } tsMnode = {0};
 
-static int32_t dnodeReadMnode() {
+static int32_t dnodeAllocMnodeReadQueue();
+static void    dnodeFreeMnodeReadQueue();
+static int32_t dnodeAllocMnodeWriteQueue();
+static void    dnodeFreeMnodeWriteQueue();
+static int32_t dnodeAllocMnodeApplyQueue();
+static void    dnodeFreeMnodeApplyQueue();
+static int32_t dnodeAllocMnodeSyncQueue();
+static void    dnodeFreeMnodeSyncQueue();
+
+static int32_t dnodeAcquireMnode() {
+  taosRLockLatch(&tsMnode.latch);
+
+  int32_t code = tsMnode.deployed ? 0 : TSDB_CODE_DND_MNODE_NOT_DEPLOYED;
+  if (code == 0) {
+    atomic_add_fetch_32(&tsMnode.refCount, 1);
+  }
+
+  taosRUnLockLatch(&tsMnode.latch);
+  return code;
+}
+
+static void dnodeReleaseMnode() { atomic_sub_fetch_32(&tsMnode.refCount, 1); }
+
+static int32_t dnodeReadMnodeFile() {
+  int32_t code = TSDB_CODE_DND_READ_MNODE_FILE_ERROR;
   int32_t len = 0;
   int32_t maxLen = 300;
   char   *content = calloc(1, maxLen + 1);
   cJSON  *root = NULL;
   FILE   *fp = NULL;
+  char    file[PATH_MAX + 20] = {0};
 
-  fp = fopen(tsMnode.file, "r");
+  snprintf(file, sizeof(file), "%s/mnode.json", tsDnodeDir);
+  fp = fopen(file, "r");
   if (!fp) {
-    dDebug("file %s not exist", tsMnode.file);
+    dDebug("file %s not exist", file);
+    code = 0;
     goto PRASE_MNODE_OVER;
   }
 
   len = (int32_t)fread(content, 1, maxLen, fp);
   if (len <= 0) {
-    dError("failed to read %s since content is null", tsMnode.file);
+    dError("failed to read %s since content is null", file);
     goto PRASE_MNODE_OVER;
   }
 
   content[len] = 0;
   root = cJSON_Parse(content);
   if (root == NULL) {
-    dError("failed to read %s since invalid json format", tsMnode.file);
+    dError("failed to read %s since invalid json format", file);
     goto PRASE_MNODE_OVER;
   }
 
   cJSON *deployed = cJSON_GetObjectItem(root, "deployed");
   if (!deployed || deployed->type != cJSON_String) {
-    dError("failed to read %s since deployed not found", tsMnode.file);
+    dError("failed to read %s since deployed not found", file);
     goto PRASE_MNODE_OVER;
   }
   tsMnode.deployed = atoi(deployed->valuestring);
 
   cJSON *dropped = cJSON_GetObjectItem(root, "dropped");
   if (!dropped || dropped->type != cJSON_String) {
-    dError("failed to read %s since dropped not found", tsMnode.file);
+    dError("failed to read %s since dropped not found", file);
     goto PRASE_MNODE_OVER;
   }
   tsMnode.dropped = atoi(dropped->valuestring);
 
-  dInfo("succcessed to read file %s", tsMnode.file);
+  code = 0;
+  dInfo("succcessed to read file %s", file);
 
 PRASE_MNODE_OVER:
   if (content != NULL) free(content);
   if (root != NULL) cJSON_Delete(root);
   if (fp != NULL) fclose(fp);
 
-  return 0;
+  return code;
 }
 
-static int32_t dnodeWriteMnode() {
-  FILE *fp = fopen(tsMnode.file, "w");
+static int32_t dnodeWriteMnodeFile() {
+  char file[PATH_MAX + 20] = {0};
+  char realfile[PATH_MAX + 20] = {0};
+  snprintf(file, sizeof(file), "%s/mnode.json.bak", tsDnodeDir);
+  snprintf(realfile, sizeof(realfile), "%s/mnode.json", tsDnodeDir);
+
+  FILE *fp = fopen(file, "w");
   if (!fp) {
-    dError("failed to write %s since %s", tsMnode.file, strerror(errno));
-    return -1;
+    dError("failed to write %s since %s", file, strerror(errno));
+    return TSDB_CODE_DND_WRITE_MNODE_FILE_ERROR;
   }
 
   int32_t len = 0;
@@ -97,197 +144,452 @@ static int32_t dnodeWriteMnode() {
   taosFsyncFile(fileno(fp));
   fclose(fp);
   free(content);
-  terrno = 0;
 
-  dInfo("successed to write %s", tsMnode.file);
+  int32_t code = taosRenameFile(file, realfile);
+  if (code != 0) {
+    dError("failed to rename %s since %s", file, tstrerror(code));
+    return TSDB_CODE_DND_WRITE_MNODE_FILE_ERROR;
+  }
+
+  dInfo("successed to write %s", realfile);
   return 0;
 }
 
-static int32_t dnodeStartMnode(SCreateMnodeMsg *pCfg) {
-  int32_t code = 0;
+static int32_t dnodeStartMnode() {
+  int32_t code = dnodeAllocMnodeReadQueue();
+  if (code != 0) {
+    return code;
+  }
 
-  if (pCfg->dnodeId != dnodeGetDnodeId()) {
-    code = TSDB_CODE_DND_DNODE_ID_NOT_MATCHED;
-    dError("failed to start mnode since %s", tstrerror(code));
+  code = dnodeAllocMnodeWriteQueue();
+  if (code != 0) {
     return code;
   }
 
-  if (tsMnode.dropped) {
-    code = TSDB_CODE_DND_MNODE_ALREADY_DROPPED;
-    dError("failed to start mnode since %s", tstrerror(code));
+  code = dnodeAllocMnodeApplyQueue();
+  if (code != 0) {
     return code;
   }
 
-  if (tsMnode.deployed) {
-    dError("failed to start mnode since its already deployed");
-    return 0;
+  code = dnodeAllocMnodeSyncQueue();
+  if (code != 0) {
+    return code;
   }
 
+  taosWLockLatch(&tsMnode.latch);
   tsMnode.deployed = 1;
-  tsMnode.dropped = 0;
+  taosWUnLockLatch(&tsMnode.latch);
 
-  code = dnodeWriteMnode();
+  return code;
+}
+
+static void dnodeStopMnode() {
+  taosWLockLatch(&tsMnode.latch);
+  tsMnode.deployed = 0;
+  taosWUnLockLatch(&tsMnode.latch);
+
+  dnodeReleaseMnode();
+
+  while (tsMnode.refCount > 0) taosMsleep(10);
+  while (!taosQueueEmpty(tsMnode.pReadQ)) taosMsleep(10);
+  while (!taosQueueEmpty(tsMnode.pApplyQ)) taosMsleep(10);
+  while (!taosQueueEmpty(tsMnode.pWriteQ)) taosMsleep(10);
+  while (!taosQueueEmpty(tsMnode.pSyncQ)) taosMsleep(10);
+
+  dnodeFreeMnodeReadQueue();
+  dnodeFreeMnodeWriteQueue();
+  dnodeFreeMnodeApplyQueue();
+  dnodeFreeMnodeSyncQueue();
+}
+
+static int32_t dnodeUnDeployMnode() {
+  tsMnode.dropped = 1;
+  int32_t code = dnodeWriteMnodeFile();
+  if (code != 0) {
+    tsMnode.dropped = 0;
+    dError("failed to undeploy mnode since %s", tstrerror(code));
+    return code;
+  }
+
+  dnodeStopMnode();
+  mnodeUnDeploy(tsMnodeDir);
+  dnodeWriteMnodeFile();
+
+  return code;
+}
+
+static int32_t dnodeDeployMnode(SMnodeCfg *pCfg) {
+  int32_t code = mnodeDeploy(tsMnodeDir, pCfg);
   if (code != 0) {
-    tsMnode.deployed = 0;
-    dError("failed to start mnode since %s", tstrerror(code));
+    dError("failed to deploy mnode since %s", tstrerror(code));
     return code;
   }
 
-  code = mnodeDeploy();
+  code = dnodeStartMnode();
   if (code != 0) {
-    tsMnode.deployed = 0;
-    dError("failed to start mnode since %s", tstrerror(code));
+    dnodeUnDeployMnode();
+    dError("failed to deploy mnode since %s", tstrerror(code));
     return code;
   }
 
-  code = mnodeStart();
+  code = dnodeWriteMnodeFile();
   if (code != 0) {
-    tsMnode.deployed = 0;
-    dError("failed to start mnode since %s", tstrerror(code));
+    dnodeUnDeployMnode();
+    dError("failed to deploy mnode since %s", tstrerror(code));
     return code;
   }
 
-  tsMnode.deployed = 1;
-  return 0;
+  dInfo("deploy mnode success");
+  return code;
 }
 
-static int32_t dnodeDropMnode(SDropMnodeMsg *pCfg) {
-  int32_t code = 0;
+static int32_t dnodeAlterMnode(SMnodeCfg *pCfg) {
+  int32_t code = dnodeAcquireMnode();
+  if (code == 0) {
+    code = mnodeAlter(pCfg);
+    dnodeReleaseMnode();
+  }
+  return code;
+}
+
+static SCreateMnodeMsg *dnodeParseCreateMnodeMsg(SRpcMsg *pRpcMsg) {
+  SCreateMnodeMsg *pMsg = pRpcMsg->pCont;
+  pMsg->dnodeId = htonl(pMsg->dnodeId);
+  for (int32_t i = 0; i < pMsg->replica; ++i) {
+    pMsg->replicas[i].port = htons(pMsg->replicas[i].port);
+  }
+  return pMsg;
+}
+
+static int32_t dnodeProcessCreateMnodeReq(SRpcMsg *pRpcMsg) {
+  SAlterMnodeMsg *pMsg = (SAlterMnodeMsg *)dnodeParseCreateMnodeMsg(pRpcMsg->pCont);
+
+  if (pMsg->dnodeId != dnodeGetDnodeId()) {
+    return TSDB_CODE_DND_MNODE_ID_NOT_MATCH_DNODE;
+  } else {
+    SMnodeCfg cfg = {0};
+    cfg.replica = pMsg->replica;
+    memcpy(cfg.replicas, pMsg->replicas, sizeof(SReplica) * sizeof(TSDB_MAX_REPLICA));
+    return dnodeDeployMnode(&cfg);
+  }
+}
+
+static int32_t dnodeProcessAlterMnodeReq(SRpcMsg *pRpcMsg) {
+  SAlterMnodeMsg *pMsg = (SAlterMnodeMsg *)dnodeParseCreateMnodeMsg(pRpcMsg->pCont);
+  if (pMsg->dnodeId != dnodeGetDnodeId()) {
+    return TSDB_CODE_DND_MNODE_ID_NOT_MATCH_DNODE;
+  } else {
+    SMnodeCfg cfg = {0};
+    cfg.replica = pMsg->replica;
+    memcpy(cfg.replicas, pMsg->replicas, sizeof(SReplica) * sizeof(TSDB_MAX_REPLICA));
+    return dnodeAlterMnode(&cfg);
+  }
+}
+
+static int32_t dnodeProcessDropMnodeReq(SRpcMsg *pMsg) {
+  SAlterMnodeMsg *pCfg = pMsg->pCont;
+  pCfg->dnodeId = htonl(pCfg->dnodeId);
 
   if (pCfg->dnodeId != dnodeGetDnodeId()) {
-    code = TSDB_CODE_DND_DNODE_ID_NOT_MATCHED;
-    dError("failed to drop mnode since %s", tstrerror(code));
-    return code;
+    return TSDB_CODE_DND_MNODE_ID_NOT_MATCH_DNODE;
+  } else {
+    return dnodeUnDeployMnode();
   }
+}
 
-  if (tsMnode.dropped) {
-    code = TSDB_CODE_DND_MNODE_ALREADY_DROPPED;
-    dError("failed to drop mnode since %s", tstrerror(code));
-    return code;
+static void dnodeProcessMnodeMgmtQueue(void *unused, SRpcMsg *pMsg) {
+  int32_t code = 0;
+
+  switch (pMsg->msgType) {
+    case TSDB_MSG_TYPE_CREATE_MNODE_IN:
+      code = dnodeProcessCreateMnodeReq(pMsg);
+      break;
+    case TSDB_MSG_TYPE_ALTER_MNODE_IN:
+      code = dnodeProcessAlterMnodeReq(pMsg);
+      break;
+    case TSDB_MSG_TYPE_DROP_MNODE_IN:
+      code = dnodeProcessDropMnodeReq(pMsg);
+      break;
+    default:
+      code = TSDB_CODE_DND_MSG_NOT_PROCESSED;
+      break;
   }
 
-  if (!tsMnode.deployed) {
-    dError("failed to drop mnode since not deployed");
-    return 0;
+  SRpcMsg rsp = {.code = code, .handle = pMsg->handle};
+  rpcSendResponse(&rsp);
+  rpcFreeCont(pMsg->pCont);
+  taosFreeQitem(pMsg);
+}
+
+static void dnodeProcessMnodeReadQueue(void *unused, SMnodeMsg *pMsg) { mnodeProcessMsg(pMsg, MN_MSG_TYPE_READ); }
+
+static void dnodeProcessMnodeWriteQueue(void *unused, SMnodeMsg *pMsg) { mnodeProcessMsg(pMsg, MN_MSG_TYPE_WRITE); }
+
+static void dnodeProcessMnodeApplyQueue(void *unused, SMnodeMsg *pMsg) { mnodeProcessMsg(pMsg, MN_MSG_TYPE_APPLY); }
+
+static void dnodeProcessMnodeSyncQueue(void *unused, SMnodeMsg *pMsg) { mnodeProcessMsg(pMsg, MN_MSG_TYPE_SYNC); }
+
+static int32_t dnodeWriteMnodeMsgToQueue(taos_queue pQueue, SRpcMsg *pRpcMsg) {
+  int32_t code = 0;
+
+  if (pQueue == NULL) {
+    code = TSDB_CODE_DND_MSG_NOT_PROCESSED;
+  } else {
+    SMnodeMsg *pMsg = mnodeInitMsg(1);
+    if (pMsg == NULL) {
+      code = TSDB_CODE_DND_OUT_OF_MEMORY;
+    } else {
+      mnodeAppendMsg(pMsg, pRpcMsg);
+      code = taosWriteQitem(pQueue, pMsg);
+    }
   }
 
-  mnodeStop();
+  if (code != TSDB_CODE_SUCCESS) {
+    SRpcMsg rsp = {.handle = pRpcMsg->handle, .code = code};
+    rpcSendResponse(&rsp);
+    rpcFreeCont(pRpcMsg->pCont);
+  }
+}
 
-  tsMnode.deployed = 0;
-  tsMnode.dropped = 1;
+void dnodeProcessMnodeMgmtMsg(SRpcMsg *pMsg, SEpSet *pEpSet) { dnodeWriteMnodeMsgToQueue(tsMnode.pMgmtQ, pMsg); }
 
-  code = dnodeWriteMnode();
-  if (code != 0) {
-    tsMnode.deployed = 1;
-    tsMnode.dropped = 0;
-    dError("failed to drop mnode since %s", tstrerror(code));
-    return code;
+void dnodeProcessMnodeWriteMsg(SRpcMsg *pMsg, SEpSet *pEpSet) {
+  if (dnodeAcquireMnode() == 0) {
+    dnodeWriteMnodeMsgToQueue(tsMnode.pWriteQ, pMsg);
+    dnodeReleaseMnode();
+  } else {
+    dnodeSendRedirectMsg(pMsg, 0);
   }
+}
 
-  mnodeUnDeploy();
+void dnodeProcessMnodeSyncMsg(SRpcMsg *pMsg, SEpSet *pEpSet) {
+  int32_t code = dnodeAcquireMnode();
+  if (code == 0) {
+    dnodeWriteMnodeMsgToQueue(tsMnode.pSyncQ, pMsg);
+    dnodeReleaseMnode();
+  } else {
+    SRpcMsg rsp = {.handle = pMsg->handle, .code = code};
+    rpcSendResponse(&rsp);
+    rpcFreeCont(pMsg->pCont);
+  }
+}
 
-  tsMnode.deployed = 0;
+void dnodeProcessMnodeReadMsg(SRpcMsg *pMsg, SEpSet *pEpSet) {
+  if (dnodeAcquireMnode() == 0) {
+    dnodeWriteMnodeMsgToQueue(tsMnode.pReadQ, pMsg);
+    dnodeReleaseMnode();
+  } else {
+    dnodeSendRedirectMsg(pMsg, 0);
+  }
+}
+
+static int32_t dnodePutMsgIntoMnodeApplyQueue(SMnodeMsg *pMsg) {
+  int32_t code = dnodeAcquireMnode();
+  if (code != 0) return code;
+
+  code = taosWriteQitem(tsMnode.pApplyQ, pMsg);
+  dnodeReleaseMnode();
+  return code;
+}
+
+static int32_t dnodeAllocMnodeMgmtQueue() {
+  tsMnode.pMgmtQ = tWorkerAllocQueue(&tsMnode.mgmtPool, NULL, (FProcessItem)dnodeProcessMnodeMgmtQueue);
+  if (tsMnode.pMgmtQ == NULL) {
+    return TSDB_CODE_DND_OUT_OF_MEMORY;
+  }
   return 0;
 }
 
-static void dnodeProcessCreateMnodeReq(SRpcMsg *pMsg) {
-  SCreateMnodeMsg *pCfg = pMsg->pCont;
-  pCfg->dnodeId = htonl(pCfg->dnodeId);
+static void dnodeFreeMnodeMgmtQueue() {
+  tWorkerFreeQueue(&tsMnode.mgmtPool, tsMnode.pMgmtQ);
+  tsMnode.pMgmtQ = NULL;
+}
 
-  int32_t code = dnodeStartMnode(pCfg);
-  SRpcMsg rspMsg = {.handle = pMsg->handle, .code = code};
-  rpcSendResponse(&rspMsg);
-  rpcFreeCont(pMsg->pCont);
+static int32_t dnodeInitMnodeMgmtWorker() {
+  SWorkerPool *pPool = &tsMnode.mgmtPool;
+  pPool->name = "mnode-mgmt";
+  pPool->min = 1;
+  pPool->max = 1;
+  return tWorkerInit(pPool);
 }
 
-static void dnodeProcessDropMnodeReq(SRpcMsg *pMsg) {
-  SDropMnodeMsg *pCfg = pMsg->pCont;
-  pCfg->dnodeId = htonl(pCfg->dnodeId);
+static void dnodeCleanupMnodeMgmtWorker() { tWorkerCleanup(&tsMnode.mgmtPool); }
 
-  int32_t code = dnodeDropMnode(pCfg);
-  SRpcMsg rspMsg = {.handle = pMsg->handle, .code = code};
-  rpcSendResponse(&rspMsg);
-  rpcFreeCont(pMsg->pCont);
+static int32_t dnodeAllocMnodeReadQueue() {
+  tsMnode.pReadQ = tWorkerAllocQueue(&tsMnode.readPool, NULL, (FProcessItem)dnodeProcessMnodeReadQueue);
+  if (tsMnode.pReadQ == NULL) {
+    return TSDB_CODE_DND_OUT_OF_MEMORY;
+  }
+  return 0;
 }
 
-static bool dnodeNeedDeployMnode() {
-  if (dnodeGetDnodeId() > 0) return false;
-  if (dnodeGetClusterId() > 0) return false;
-  if (strcmp(tsFirst, tsLocalEp) != 0) return false;
-  return true;
+static void dnodeFreeMnodeReadQueue() {
+  tWorkerFreeQueue(&tsMnode.readPool, tsMnode.pReadQ);
+  tsMnode.pReadQ = NULL;
 }
 
-int32_t dnodeInitMnode() {
-  tsMnode.dropped = 0;
-  tsMnode.deployed = 0;
-  snprintf(tsMnode.file, sizeof(tsMnode.file), "%s/mnode.json", tsDnodeDir);
+static int32_t dnodeInitMnodeReadWorker() {
+  SWorkerPool *pPool = &tsMnode.readPool;
+  pPool->name = "mnode-read";
+  pPool->min = 0;
+  pPool->max = 1;
+  return tWorkerInit(pPool);
+}
+
+static void dnodeCleanupMnodeReadWorker() { tWorkerCleanup(&tsMnode.readPool); }
+
+static int32_t dnodeAllocMnodeWriteQueue() {
+  tsMnode.pWriteQ = tWorkerAllocQueue(&tsMnode.writePool, NULL, (FProcessItem)dnodeProcessMnodeWriteQueue);
+  if (tsMnode.pWriteQ == NULL) {
+    return TSDB_CODE_DND_OUT_OF_MEMORY;
+  }
+  return 0;
+}
+
+static void dnodeFreeMnodeWriteQueue() {
+  tWorkerFreeQueue(&tsMnode.writePool, tsMnode.pWriteQ);
+  tsMnode.pWriteQ = NULL;
+}
+
+static int32_t dnodeAllocMnodeApplyQueue() {
+  tsMnode.pApplyQ = tWorkerAllocQueue(&tsMnode.writePool, NULL, (FProcessItem)dnodeProcessMnodeApplyQueue);
+  if (tsMnode.pApplyQ == NULL) {
+    return TSDB_CODE_DND_OUT_OF_MEMORY;
+  }
+  return 0;
+}
+
+static void dnodeFreeMnodeApplyQueue() {
+  tWorkerFreeQueue(&tsMnode.writePool, tsMnode.pApplyQ);
+  tsMnode.pApplyQ = NULL;
+}
+
+static int32_t dnodeInitMnodeWriteWorker() {
+  SWorkerPool *pPool = &tsMnode.writePool;
+  pPool->name = "mnode-write";
+  pPool->min = 0;
+  pPool->max = 1;
+  return tWorkerInit(pPool);
+}
+
+static void dnodeCleanupMnodeWriteWorker() { tWorkerCleanup(&tsMnode.writePool); }
+
+static int32_t dnodeAllocMnodeSyncQueue() {
+  tsMnode.pSyncQ = tWorkerAllocQueue(&tsMnode.syncPool, NULL, (FProcessItem)dnodeProcessMnodeSyncQueue);
+  if (tsMnode.pSyncQ == NULL) {
+    return TSDB_CODE_DND_OUT_OF_MEMORY;
+  }
+  return 0;
+}
+
+static void dnodeFreeMnodeSyncQueue() {
+  tWorkerFreeQueue(&tsMnode.syncPool, tsMnode.pSyncQ);
+  tsMnode.pSyncQ = NULL;
+}
+
+static int32_t dnodeInitMnodeSyncWorker() {
+  SWorkerPool *pPool = &tsMnode.syncPool;
+  pPool->name = "mnode-sync";
+  pPool->min = 0;
+  pPool->max = 1;
+  return tWorkerInit(pPool);
+}
+
+static void dnodeCleanupMnodeSyncWorker() { tWorkerCleanup(&tsMnode.syncPool); }
+
+static int32_t dnodeInitMnodeModule() {
+  taosInitRWLatch(&tsMnode.latch);
 
   SMnodePara para;
-  para.fp.GetDnodeEp = dnodeGetDnodeEp;
-  para.fp.SendMsgToDnode = dnodeSendMsgToDnode;
-  para.fp.SendMsgToMnode = dnodeSendMsgToMnode;
-  para.fp.SendRedirectMsg = dnodeSendRedirectMsg;
   para.dnodeId = dnodeGetDnodeId();
   para.clusterId = dnodeGetClusterId();
+  para.SendMsgToDnode = dnodeSendMsgToDnode;
+  para.SendMsgToMnode = dnodeSendMsgToMnode;
+  para.SendRedirectMsg = dnodeSendRedirectMsg;
 
-  int32_t code = mnodeInit(para);
-  if (code != 0) {
-    dError("failed to init mnode module since %s", tstrerror(code));
-    return code;
-  }
+  return mnodeInit(para);
+}
 
-  code = dnodeReadMnode();
+static void dnodeCleanupMnodeModule() { mnodeCleanup(); }
+
+static bool dnodeNeedDeployMnode() {
+  if (dnodeGetDnodeId() > 0) return false;
+  if (dnodeGetClusterId() > 0) return false;
+  if (strcmp(tsFirst, tsLocalEp) != 0) return false;
+  return true;
+}
+
+static int32_t dnodeOpenMnode() {
+  int32_t code = dnodeReadMnodeFile();
   if (code != 0) {
-    dError("failed to read file:%s since %s", tsMnode.file, tstrerror(code));
+    dError("failed to read open mnode since %s", tstrerror(code));
     return code;
   }
 
   if (tsMnode.dropped) {
-    dError("mnode already dropped, undeploy it");
-    mnodeUnDeploy();
-    return 0;
+    dInfo("mnode already dropped, undeploy it");
+    return dnodeUnDeployMnode();
   }
 
   if (!tsMnode.deployed) {
     bool needDeploy = dnodeNeedDeployMnode();
-    if (needDeploy) {
-      code = mnodeDeploy();
-    } else {
-      return 0;
-    }
-
-    if (code != 0) {
-      dError("failed to deploy mnode since %s", tstrerror(code));
-      return code;
-    }
-
-    tsMnode.deployed = 1;
+    if (!needDeploy) return 0;
+
+    dInfo("start to deploy mnode");
+    SMnodeCfg cfg = {.replica = 1};
+    cfg.replicas[0].port = tsServerPort;
+    tstrncpy(cfg.replicas[0].fqdn, tsLocalFqdn, TSDB_FQDN_LEN);
+    return dnodeDeployMnode(&cfg);
+  } else {
+    dInfo("start to open mnode");
+    return dnodeStartMnode();
   }
-
-  return mnodeStart();
 }
 
-void dnodeCleanupMnode() {
-  if (tsMnode.deployed) {
-    mnodeStop();
+static void dnodeCloseMnode() {
+  if (dnodeAcquireMnode() == 0) {
+    dnodeStopMnode();
   }
+}
 
-  mnodeCleanup();
+int32_t dnodeInitMnode() {
+  dInfo("dnode-mnode start to init");
+
+  SSteps *pSteps = taosStepInit(6, dnodeReportStartup);
+  taosStepAdd(pSteps, "dnode-mnode-env", dnodeInitMnodeModule, dnodeCleanupMnodeModule);
+  taosStepAdd(pSteps, "dnode-mnode-mgmt", dnodeInitMnodeMgmtWorker, dnodeCleanupMnodeMgmtWorker);
+  taosStepAdd(pSteps, "dnode-mnode-read", dnodeInitMnodeReadWorker, dnodeCleanupMnodeReadWorker);
+  taosStepAdd(pSteps, "dnode-mnode-write", dnodeInitMnodeWriteWorker, dnodeCleanupMnodeWriteWorker);
+  taosStepAdd(pSteps, "dnode-mnode-sync", dnodeInitMnodeSyncWorker, dnodeCleanupMnodeSyncWorker);
+  taosStepAdd(pSteps, "dnode-mnode", dnodeOpenMnode, dnodeCloseMnode);
+
+  tsMnode.pSteps = pSteps;
+  int32_t code = taosStepExec(pSteps);
+
+  if (code != 0) {
+    dError("dnode-mnode init failed since %s", tstrerror(code));
+  } else {
+    dInfo("dnode-mnode is initialized");
+  }
 }
 
-void dnodeProcessMnodeMsg(SRpcMsg *pMsg, SEpSet *pEpSet) {
-  switch (pMsg->msgType) {
-    case TSDB_MSG_TYPE_CREATE_MNODE_IN:
-      dnodeProcessCreateMnodeReq(pMsg);
-      break;
-    case TSDB_MSG_TYPE_DROP_MNODE_IN:
-      dnodeProcessDropMnodeReq(pMsg);
-      break;
-    default:
-      mnodeProcessMsg(pMsg);
+void dnodeCleanupMnode() {
+  if (tsMnode.pSteps == NULL) {
+    dInfo("dnode-mnode start to clean up");
+    taosStepCleanup(tsMnode.pSteps);
+    tsMnode.pSteps = NULL;
+    dInfo("dnode-mnode is cleaned up");
   }
 }
 
 int32_t dnodeGetUserAuthFromMnode(char *user, char *spi, char *encrypt, char *secret, char *ckey) {
-  return mnodeRetriveAuth(user, spi, encrypt, secret, ckey);
+  int32_t code = dnodeAcquireMnode();
+  if (code != 0) {
+    dTrace("failed to get user auth since mnode not deployed");
+    return code;
+  }
+
+  code = mnodeRetriveAuth(user, spi, encrypt, secret, ckey);
+  dnodeReleaseMnode();
+  return code;
 }
\ No newline at end of file
diff --git a/source/dnode/mgmt/src/dnodeTransport.c b/source/dnode/mgmt/src/dnodeTransport.c
index 265efe3070f3a8735e929b7f76971fbb2acb9b87..475470b574cf836081fc96d74d3c75c083a24c1b 100644
--- a/source/dnode/mgmt/src/dnodeTransport.c
+++ b/source/dnode/mgmt/src/dnodeTransport.c
@@ -51,76 +51,78 @@ static void dnodeInitMsgFp() {
   tsTrans.msgFp[TSDB_MSG_TYPE_MQ_RESET] = dnodeProcessVnodeWriteMsg;
   
   // msg from client to mnode
-  tsTrans.msgFp[TSDB_MSG_TYPE_CONNECT] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_ACCT] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_ACCT] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_ACCT] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_USER] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_USER] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_USER] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_DNODE] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CONFIG_DNODE] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_DNODE] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_DB] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_DB] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_USE_DB] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_DB] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_SYNC_DB] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_TOPIC] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_TOPIC] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_TOPIC] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_FUNCTION] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_FUNCTION] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_FUNCTION] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_STABLE] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_STABLE] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_STABLE] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_STABLE_VGROUP] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_KILL_QUERY] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_KILL_CONN] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_HEARTBEAT] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_SHOW] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_SHOW_RETRIEVE] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_SHOW_RETRIEVE_FUNC] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_COMPACT_VNODE] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CONNECT] = dnodeProcessMnodeReadMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_ACCT] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_ACCT] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_ACCT] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_USER] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_USER] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_USER] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_DNODE] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CONFIG_DNODE] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_DNODE] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_DB] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_DB] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_USE_DB] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_DB] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_SYNC_DB] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_TOPIC] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_TOPIC] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_TOPIC] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_FUNCTION] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_FUNCTION] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_FUNCTION] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_STABLE] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_STABLE] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_STABLE] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_STABLE_VGROUP] = dnodeProcessMnodeReadMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_KILL_QUERY] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_KILL_CONN] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_HEARTBEAT] = dnodeProcessMnodeReadMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_SHOW] = dnodeProcessMnodeReadMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_SHOW_RETRIEVE] = dnodeProcessMnodeReadMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_SHOW_RETRIEVE_FUNC] = dnodeProcessMnodeReadMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_COMPACT_VNODE] = dnodeProcessMnodeWriteMsg;
 
   // message from client to dnode
   tsTrans.msgFp[TSDB_MSG_TYPE_NETWORK_TEST] = dnodeProcessDnodeMsg;
 
   // message from mnode to vnode
   tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_STABLE_IN] = dnodeProcessVnodeWriteMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_STABLE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_STABLE_IN_RSP] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_STABLE_IN] = dnodeProcessVnodeWriteMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_STABLE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_STABLE_IN_RSP] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_DROP_STABLE_IN] = dnodeProcessVnodeWriteMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_STABLE_IN] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_STABLE_IN] = dnodeProcessMnodeWriteMsg;
 
   // message from mnode to dnode
   tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_VNODE_IN] = dnodeProcessVnodeMgmtMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_VNODE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_VNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_VNODE_IN] = dnodeProcessVnodeMgmtMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_VNODE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_VNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_DROP_VNODE_IN] = dnodeProcessVnodeMgmtMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_VNODE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_VNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_SYNC_VNODE_IN] = dnodeProcessVnodeMgmtMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_SYNC_VNODE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_SYNC_VNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_AUTH_VNODE_IN] = dnodeProcessVnodeMgmtMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_AUTH_VNODE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_AUTH_VNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_COMPACT_VNODE_IN] = dnodeProcessVnodeMgmtMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_COMPACT_VNODE_IN_RSP] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_MNODE_IN] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_MNODE_IN_RSP] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_MNODE_IN] = dnodeProcessMnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_MNODE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_COMPACT_VNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_MNODE_IN] = dnodeProcessMnodeMgmtMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CREATE_MNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_MNODE_IN] = dnodeProcessMnodeMgmtMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_ALTER_MNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_MNODE_IN] = dnodeProcessMnodeMgmtMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_DROP_MNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_CONFIG_DNODE_IN] = dnodeProcessDnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_CONFIG_DNODE_IN_RSP] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_CONFIG_DNODE_IN_RSP] = dnodeProcessMnodeWriteMsg;
 
   // message from dnode to mnode
-  tsTrans.msgFp[TSDB_MSG_TYPE_AUTH] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_AUTH] = dnodeProcessMnodeReadMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_AUTH_RSP] = dnodeProcessDnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_GRANT] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_GRANT] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_GRANT_RSP] = dnodeProcessDnodeMsg;
-  tsTrans.msgFp[TSDB_MSG_TYPE_STATUS] = dnodeProcessMnodeMsg;
+  tsTrans.msgFp[TSDB_MSG_TYPE_STATUS] = dnodeProcessMnodeWriteMsg;
   tsTrans.msgFp[TSDB_MSG_TYPE_STATUS_RSP] = dnodeProcessDnodeMsg;
 }
 
diff --git a/source/dnode/mgmt/src/dnodeVnodes.c b/source/dnode/mgmt/src/dnodeVnodes.c
index 8bf80ccff89df15a2cd01316e89e9ab743da169d..c23773f92fedf07828087a7b818877f51f34147c 100644
--- a/source/dnode/mgmt/src/dnodeVnodes.c
+++ b/source/dnode/mgmt/src/dnodeVnodes.c
@@ -983,7 +983,7 @@ static int32_t dnodeInitVnodeModule() {
 int32_t dnodeInitVnodes() {
   dInfo("dnode-vnodes start to init");
 
-  SSteps *pSteps = taosStepInit(3, dnodeReportStartup);
+  SSteps *pSteps = taosStepInit(6, dnodeReportStartup);
   taosStepAdd(pSteps, "dnode-vnode-env", dnodeInitVnodeModule, vnodeCleanup);
   taosStepAdd(pSteps, "dnode-vnode-mgmt", dnodeInitVnodeMgmtWorker, dnodeCleanupVnodeMgmtWorker);
   taosStepAdd(pSteps, "dnode-vnode-read", dnodeInitVnodeReadWorker, dnodeCleanupVnodeReadWorker);
diff --git a/source/dnode/mnode/inc/mnodeInt.h b/source/dnode/mnode/inc/mnodeInt.h
index 5fcd7173eea6effbb5a2821f9d676159d1132287..77ed79f82c99ea432b44a946b58bd3b373428d23 100644
--- a/source/dnode/mnode/inc/mnodeInt.h
+++ b/source/dnode/mnode/inc/mnodeInt.h
@@ -32,7 +32,6 @@ EMnStatus mnodeGetStatus();
 void mnodeSendMsgToDnode(struct SEpSet *epSet, struct SRpcMsg *rpcMsg);
 void mnodeSendMsgToMnode(struct SRpcMsg *rpcMsg);
 void mnodeSendRedirectMsg(struct SRpcMsg *rpcMsg, bool forShell);
-void mnodeGetDnodeEp(int32_t dnodeId, char *ep, char *fqdn, uint16_t *port);
 
 #ifdef __cplusplus
 }
diff --git a/source/dnode/mnode/inc/mnodeWorker.h b/source/dnode/mnode/inc/mnodeWorker.h
index 7663df6559603e95360f12e0a2f0a2269c3c4611..8477af6b7203d0a3d9a49adc73f7ec6a08d564c5 100644
--- a/source/dnode/mnode/inc/mnodeWorker.h
+++ b/source/dnode/mnode/inc/mnodeWorker.h
@@ -24,7 +24,6 @@ extern "C" {
 
 int32_t mnodeInitWorker();
 void    mnodeCleanupWorker();
-void    mnodeProcessMsg(SRpcMsg *rpcMsg);
 void    mnodeSendRsp(SMnMsg *pMsg, int32_t code);
 void    mnodeReDispatchToWriteQueue(SMnMsg *pMsg);
 
diff --git a/source/dnode/mnode/src/mnodeTelem.c b/source/dnode/mnode/src/mnodeTelem.c
index 8b8e4f9ce0931637fb91f9798fd2e79d42d9729d..a3977f5b1761640571b2c38f09b3ba7865a9fa51 100644
--- a/source/dnode/mnode/src/mnodeTelem.c
+++ b/source/dnode/mnode/src/mnodeTelem.c
@@ -172,21 +172,21 @@ static void mnodeAddVersionInfo(SBufferWriter* bw) {
 }
 
 static void mnodeAddRuntimeInfo(SBufferWriter* bw) {
-  SMnodeStat stat = {0};
-  if (mnodeGetStatistics(&stat) != 0) {
+  SMnodeLoad load = {0};
+  if (mnodeGetLoad(&load) != 0) {
     return;
   }
 
-  mnodeAddIntField(bw, "numOfDnode", stat.numOfDnode);
-  mnodeAddIntField(bw, "numOfMnode", stat.numOfMnode);
-  mnodeAddIntField(bw, "numOfVgroup", stat.numOfVgroup);
-  mnodeAddIntField(bw, "numOfDatabase", stat.numOfDatabase);
-  mnodeAddIntField(bw, "numOfSuperTable", stat.numOfSuperTable);
-  mnodeAddIntField(bw, "numOfChildTable", stat.numOfChildTable);
-  mnodeAddIntField(bw, "numOfColumn", stat.numOfColumn);
-  mnodeAddIntField(bw, "numOfPoint", stat.totalPoints);
-  mnodeAddIntField(bw, "totalStorage", stat.totalStorage);
-  mnodeAddIntField(bw, "compStorage", stat.compStorage);
+  mnodeAddIntField(bw, "numOfDnode", load.numOfDnode);
+  mnodeAddIntField(bw, "numOfMnode", load.numOfMnode);
+  mnodeAddIntField(bw, "numOfVgroup", load.numOfVgroup);
+  mnodeAddIntField(bw, "numOfDatabase", load.numOfDatabase);
+  mnodeAddIntField(bw, "numOfSuperTable", load.numOfSuperTable);
+  mnodeAddIntField(bw, "numOfChildTable", load.numOfChildTable);
+  mnodeAddIntField(bw, "numOfColumn", load.numOfColumn);
+  mnodeAddIntField(bw, "numOfPoint", load.totalPoints);
+  mnodeAddIntField(bw, "totalStorage", load.totalStorage);
+  mnodeAddIntField(bw, "compStorage", load.compStorage);
 }
 
 static void mnodeSendTelemetryReport() {
diff --git a/source/dnode/mnode/src/mnodeWorker.c b/source/dnode/mnode/src/mnodeWorker.c
index e4b4c47ddf082dc74a7273784dd05a47a29f1baa..bdf0e869fc4732b339e677609a686076e9533d82 100644
--- a/source/dnode/mnode/src/mnodeWorker.c
+++ b/source/dnode/mnode/src/mnodeWorker.c
@@ -39,7 +39,7 @@ static struct {
   void (*msgFp[TSDB_MSG_TYPE_MAX])(SRpcMsg *pMsg);
 } tsMworker = {0};
 
-static SMnMsg *mnodeInitMsg(SRpcMsg *pRpcMsg) {
+static SMnMsg *mnodeInitMsg2(SRpcMsg *pRpcMsg) {
   int32_t    size = sizeof(SMnMsg) + pRpcMsg->contLen;
   SMnMsg *pMsg = taosAllocateQitem(size);
 
@@ -62,7 +62,7 @@ static SMnMsg *mnodeInitMsg(SRpcMsg *pRpcMsg) {
   return pMsg;
 }
 
-static void mnodeCleanupMsg(SMnMsg *pMsg) {
+static void mnodeCleanupMsg2(SMnMsg *pMsg) {
   if (pMsg == NULL) return;
   if (pMsg->rpcMsg.pCont != pMsg->pCont) {
     tfree(pMsg->rpcMsg.pCont);
@@ -75,7 +75,7 @@ static void mnodeDispatchToWriteQueue(SRpcMsg *pRpcMsg) {
   if (mnodeGetStatus() != MN_STATUS_READY || tsMworker.writeQ == NULL) {
     mnodeSendRedirectMsg(pRpcMsg, true);
   } else {
-    SMnMsg *pMsg = mnodeInitMsg(pRpcMsg);
+    SMnMsg *pMsg = mnodeInitMsg2(pRpcMsg);
     if (pMsg == NULL) {
       SRpcMsg rpcRsp = {.handle = pRpcMsg->handle, .code = TSDB_CODE_MND_INVALID_USER};
       rpcSendResponse(&rpcRsp);
@@ -91,7 +91,7 @@ static void mnodeDispatchToWriteQueue(SRpcMsg *pRpcMsg) {
 void mnodeReDispatchToWriteQueue(SMnMsg *pMsg) {
   if (mnodeGetStatus() != MN_STATUS_READY || tsMworker.writeQ == NULL) {
     mnodeSendRedirectMsg(&pMsg->rpcMsg, true);
-    mnodeCleanupMsg(pMsg);
+    mnodeCleanupMsg2(pMsg);
   } else {
     taosWriteQitem(tsMworker.writeQ, pMsg);
   }
@@ -101,7 +101,7 @@ static void mnodeDispatchToReadQueue(SRpcMsg *pRpcMsg) {
   if (mnodeGetStatus() != MN_STATUS_READY || tsMworker.readQ == NULL) {
     mnodeSendRedirectMsg(pRpcMsg, true);
   } else {
-    SMnMsg *pMsg = mnodeInitMsg(pRpcMsg);
+    SMnMsg *pMsg = mnodeInitMsg2(pRpcMsg);
     if (pMsg == NULL) {
       SRpcMsg rpcRsp = {.handle = pRpcMsg->handle, .code = TSDB_CODE_MND_INVALID_USER};
       rpcSendResponse(&rpcRsp);
@@ -118,7 +118,7 @@ static void mnodeDispatchToPeerQueue(SRpcMsg *pRpcMsg) {
   if (mnodeGetStatus() != MN_STATUS_READY || tsMworker.peerReqQ == NULL) {
     mnodeSendRedirectMsg(pRpcMsg, false);
   } else {
-    SMnMsg *pMsg = mnodeInitMsg(pRpcMsg);
+    SMnMsg *pMsg = mnodeInitMsg2(pRpcMsg);
     if (pMsg == NULL) {
       SRpcMsg rpcRsp = {.handle = pRpcMsg->handle, .code = TSDB_CODE_MND_INVALID_USER};
       rpcSendResponse(&rpcRsp);
@@ -133,7 +133,7 @@ static void mnodeDispatchToPeerQueue(SRpcMsg *pRpcMsg) {
 }
 
 void mnodeDispatchToPeerRspQueue(SRpcMsg *pRpcMsg) {
-  SMnMsg *pMsg = mnodeInitMsg(pRpcMsg);
+  SMnMsg *pMsg = mnodeInitMsg2(pRpcMsg);
   if (pMsg == NULL) {
     SRpcMsg rpcRsp = {.handle = pRpcMsg->handle, .code = TSDB_CODE_MND_INVALID_USER};
     rpcSendResponse(&rpcRsp);
@@ -162,7 +162,7 @@ void mnodeSendRsp(SMnMsg *pMsg, int32_t code) {
   };
 
   rpcSendResponse(&rpcRsp);
-  mnodeCleanupMsg(pMsg);
+  mnodeCleanupMsg2(pMsg);
 }
 
 static void mnodeInitMsgFp() {
@@ -405,7 +405,7 @@ static void mnodeProcessPeerRsp(SMnMsg *pMsg, void *unused) {
 
   if (!mnodeIsMaster()) {
     mError("msg:%p, ahandle:%p type:%s not processed for not master", pRpcMsg, pRpcMsg->ahandle, taosMsg[msgType]);
-    mnodeCleanupMsg(pMsg);
+    mnodeCleanupMsg2(pMsg);
   }
 
   if (tsMworker.peerRspFp[msgType]) {
@@ -414,7 +414,7 @@ static void mnodeProcessPeerRsp(SMnMsg *pMsg, void *unused) {
     mError("msg:%p, ahandle:%p type:%s is not processed", pRpcMsg, pRpcMsg->ahandle, taosMsg[msgType]);
   }
 
-  mnodeCleanupMsg(pMsg);
+  mnodeCleanupMsg2(pMsg);
 }
 
 int32_t mnodeInitWorker() {
@@ -486,10 +486,9 @@ void mnodeCleanupWorker() {
   mInfo("mnode worker is closed");
 }
 
-void mnodeProcessMsg(SRpcMsg *pMsg) {
-  if (tsMworker.msgFp[pMsg->msgType]) {
-    (*tsMworker.msgFp[pMsg->msgType])(pMsg);
-  } else {
-    assert(0);
-  }
-}
+SMnodeMsg *mnodeInitMsg(int32_t msgNum) { return NULL; }
+
+int32_t mnodeAppendMsg(SMnodeMsg *pMsg, SRpcMsg *pRpcMsg) { return 0; }
+
+void mnodeCleanupMsg(SMnodeMsg *pMsg) {}
+void mnodeProcessMsg(SMnodeMsg *pMsg, EMnMsgType msgType) {}
diff --git a/source/dnode/mnode/src/mondeInt.c b/source/dnode/mnode/src/mondeInt.c
index 669273d8dc8cc8adc6982813e448642ed6957f03..eed710a1bd7f2bda371bd6c43a0333f2addfc445 100644
--- a/source/dnode/mnode/src/mondeInt.c
+++ b/source/dnode/mnode/src/mondeInt.c
@@ -37,48 +37,42 @@
 #include "mnodeTelem.h"
 
 static struct {
-  int32_t  state;
-  int32_t  dnodeId;
-  int64_t  clusterId;
-  tmr_h    timer;
-  SMnodeFp fp;
-  SSteps * steps1;
-  SSteps * steps2;
+  int32_t    state;
+  int32_t    dnodeId;
+  int64_t    clusterId;
+  tmr_h      timer;
+  SSteps    *steps1;
+  SSteps    *steps2;
+  SMnodePara para;
 } tsMint;
 
 tmr_h mnodeGetTimer() { return tsMint.timer; }
 
-int32_t mnodeGetDnodeId() { return tsMint.dnodeId; }
+int32_t mnodeGetDnodeId() { return tsMint.para.dnodeId; }
 
-int64_t mnodeGetClusterId() { return tsMint.clusterId; }
+int64_t mnodeGetClusterId() { return tsMint.para.clusterId; }
 
 EMnStatus mnodeGetStatus() { return tsMint.state; }
 
 void mnodeSendMsgToDnode(struct SEpSet *epSet, struct SRpcMsg *rpcMsg) {
-  (*tsMint.fp.SendMsgToDnode)(epSet, rpcMsg);
+  (*tsMint.para.SendMsgToDnode)(epSet, rpcMsg);
 }
 
-void mnodeSendMsgToMnode(struct SRpcMsg *rpcMsg) { return (*tsMint.fp.SendMsgToMnode)(rpcMsg); }
+void mnodeSendMsgToMnode(struct SRpcMsg *rpcMsg) { return (*tsMint.para.SendMsgToMnode)(rpcMsg); }
 
-void mnodeSendRedirectMsg(struct SRpcMsg *rpcMsg, bool forShell) { (*tsMint.fp.SendRedirectMsg)(rpcMsg, forShell); }
+void mnodeSendRedirectMsg(struct SRpcMsg *rpcMsg, bool forShell) { (*tsMint.para.SendRedirectMsg)(rpcMsg, forShell); }
 
-void mnodeGetDnodeEp(int32_t dnodeId, char *ep, char *fqdn, uint16_t *port) {
-  (*tsMint.fp.GetDnodeEp)(dnodeId, ep, fqdn, port);
-}
-
-int32_t mnodeGetStatistics(SMnodeStat *stat) { return 0; }
+int32_t mnodeGetLoad(SMnodeLoad *pLoad) { return 0; }
 
 static int32_t mnodeSetPara(SMnodePara para) {
-  tsMint.fp = para.fp;
-  tsMint.dnodeId = para.dnodeId;
-  tsMint.clusterId = para.clusterId;
+  tsMint.para = para;
 
-  if (tsMint.fp.SendMsgToDnode == NULL) return -1;
-  if (tsMint.fp.SendMsgToMnode == NULL) return -1;
-  if (tsMint.fp.SendRedirectMsg == NULL) return -1;
-  if (tsMint.fp.GetDnodeEp == NULL) return -1;
-  if (tsMint.dnodeId < 0) return -1;
-  if (tsMint.clusterId < 0) return -1;
+  if (tsMint.para.SendMsgToDnode == NULL) return -1;
+  if (tsMint.para.SendMsgToMnode == NULL) return -1;
+  if (tsMint.para.SendRedirectMsg == NULL) return -1;
+  if (tsMint.para.PutMsgIntoApplyQueue == NULL) return -1;
+  if (tsMint.para.dnodeId < 0) return -1;
+  if (tsMint.para.clusterId < 0) return -1;
 
   return 0;
 }
@@ -142,13 +136,13 @@ static void mnodeCleanupStep1() { taosStepCleanup(tsMint.steps1); }
 static void mnodeCleanupStep2() { taosStepCleanup(tsMint.steps2); }
 
 static bool mnodeNeedDeploy() {
-  if (tsMint.dnodeId > 0) return false;
-  if (tsMint.clusterId > 0) return false;
+  if (tsMint.para.dnodeId > 0) return false;
+  if (tsMint.para.clusterId > 0) return false;
   if (strcmp(tsFirst, tsLocalEp) != 0) return false;
   return true;
 }
 
-int32_t mnodeDeploy() {
+int32_t mnodeDeploy(char *path, SMnodeCfg *pCfg) {
   if (tsMint.state != MN_STATUS_UNINIT) {
     mError("failed to deploy mnode since its deployed");
     return 0;
@@ -156,7 +150,7 @@ int32_t mnodeDeploy() {
     tsMint.state = MN_STATUS_INIT;
   }
 
-  if (tsMint.dnodeId <= 0 || tsMint.clusterId <= 0) {
+  if (tsMint.para.dnodeId <= 0 || tsMint.para.clusterId <= 0) {
     mError("failed to deploy mnode since cluster not ready");
     return TSDB_CODE_MND_NOT_READY;
   }
@@ -183,7 +177,7 @@ int32_t mnodeDeploy() {
   return 0;
 }
 
-void mnodeUnDeploy() {
+void mnodeUnDeploy(char *path) {
   sdbUnDeploy();
   mnodeCleanup();
 }
@@ -251,5 +245,6 @@ void mnodeCleanup() {
   }
 }
 
-int32_t mnodeStart() { return 0; }
+int32_t mnodeStart(char *path, SMnodeCfg *pCfg) { return 0; }
+int32_t mnodeAlter(SMnodeCfg *pCfg) { return 0; }
 void    mnodeStop() {}
\ No newline at end of file
diff --git a/source/dnode/vnode/tq/CMakeLists.txt b/source/dnode/vnode/tq/CMakeLists.txt
index 441fe46244587eaa2d35457db0d955a9d981dc80..f9e86adc73bfe53b0d65116c80cc74657b37a4bb 100644
--- a/source/dnode/vnode/tq/CMakeLists.txt
+++ b/source/dnode/vnode/tq/CMakeLists.txt
@@ -12,3 +12,7 @@ target_link_libraries(
     PUBLIC os
     PUBLIC util
 )
+
+if(${BUILD_TEST})
+    add_subdirectory(test)
+endif(${BUILD_TEST})
diff --git a/source/dnode/vnode/tq/inc/tqMetaStore.h b/source/dnode/vnode/tq/inc/tqMetaStore.h
index 65429f7af29369b3f4192629c6b165a08cb0d3ab..52cc76740996b2cf6da202229f61cb5e2374e8c8 100644
--- a/source/dnode/vnode/tq/inc/tqMetaStore.h
+++ b/source/dnode/vnode/tq/inc/tqMetaStore.h
@@ -19,6 +19,11 @@
 #include "os.h"
 #include "tq.h"
 
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #define TQ_BUCKET_SIZE 0xFF
 #define TQ_PAGE_SIZE 4096
 //key + offset + size
@@ -32,9 +37,23 @@ inline static int TqEmptyTail() { //16
   return TQ_PAGE_SIZE - TqMaxEntryOnePage();
 }
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+#define TQ_ACTION_CONST      0
+#define TQ_ACTION_INUSE      1
+#define TQ_ACTION_INUSE_CONT 2
+#define TQ_ACTION_INTXN      3
+
+#define TQ_SVER              0
+
+static const int8_t TQ_CONST_DELETE = TQ_ACTION_CONST;
+#define TQ_DELETE_TOKEN  (void*)&TQ_CONST_DELETE
+
+typedef struct TqSerializedHead {
+  int16_t ver;
+  int16_t action;
+  int32_t checksum;
+  int64_t ssize;
+  char    content[];
+} TqSerializedHead;
 
 typedef struct TqMetaHandle {
   int64_t key;
@@ -59,30 +78,33 @@ typedef struct TqMetaStore {
   TqMetaList* unpersistHead;
   int fileFd; //TODO:temporaral use, to be replaced by unified tfile
   int idxFd;  //TODO:temporaral use, to be replaced by unified tfile
-  int (*serializer)(TqGroupHandle*, void**);
-  const void* (*deserializer)(const void*, TqGroupHandle*);
+  char* dirPath;
+  int (*serializer)(const void* pObj, TqSerializedHead** ppHead);
+  const void* (*deserializer)(const TqSerializedHead* pHead, void** ppObj);
   void  (*deleter)(void*);
 } TqMetaStore;
 
 TqMetaStore*  tqStoreOpen(const char* path,
-    int serializer(TqGroupHandle*, void**),
-    const void* deserializer(const void*, TqGroupHandle*),
-    void deleter(void*));
+    int serializer(const void* pObj, TqSerializedHead** ppHead),
+    const void* deserializer(const TqSerializedHead* pHead, void** ppObj),
+    void deleter(void* pObj));
 int32_t       tqStoreClose(TqMetaStore*);
 //int32_t       tqStoreDelete(TqMetaStore*);
 //int32_t       TqStoreCommitAll(TqMetaStore*);
 int32_t       tqStorePersist(TqMetaStore*);
 
-TqMetaHandle* tqHandleGet(TqMetaStore*, int64_t key);
-int32_t       tqHandlePut(TqMetaStore*, int64_t key, void* value);
+void*   tqHandleGet(TqMetaStore*, int64_t key);
+int32_t tqHandleMovePut(TqMetaStore*, int64_t key, void* value);
+int32_t tqHandleCopyPut(TqMetaStore*, int64_t key, void* value, size_t vsize);
 //do commit
-int32_t       tqHandleCommit(TqMetaStore*, int64_t key);
+int32_t tqHandleCommit(TqMetaStore*, int64_t key);
 //delete uncommitted
-int32_t       tqHandleAbort(TqMetaStore*, int64_t key);
-//delete committed
-int32_t       tqHandleDel(TqMetaStore*, int64_t key);
+int32_t tqHandleAbort(TqMetaStore*, int64_t key);
+//delete committed kv pair
+//notice that a delete action still needs to be committed
+int32_t tqHandleDel(TqMetaStore*, int64_t key);
 //delete both committed and uncommitted
-int32_t       tqHandleClear(TqMetaStore*, int64_t key);
+int32_t tqHandleClear(TqMetaStore*, int64_t key);
 
 #ifdef __cplusplus
 }
diff --git a/source/dnode/vnode/tq/src/tqMetaStore.c b/source/dnode/vnode/tq/src/tqMetaStore.c
index 72edf10a1f8be4d41ca4c32ee15618b1402a9cd8..a4c2b904919acbede20ec86fc51efb10f1f75ba3 100644
--- a/source/dnode/vnode/tq/src/tqMetaStore.c
+++ b/source/dnode/vnode/tq/src/tqMetaStore.c
@@ -14,6 +14,7 @@
  */
 #include "tqMetaStore.h"
 //TODO:replace by an abstract file layer
+#include "osDir.h"
 #include <fcntl.h>
 #include <string.h>
 #include <unistd.h>
@@ -22,8 +23,18 @@
 #define TQ_IDX_NAME  "tq.idx"
 
 
-static int32_t       tqHandlePutCommitted(TqMetaStore*, int64_t key, void* value);
-static TqMetaHandle* tqHandleGetUncommitted(TqMetaStore*, int64_t key);
+static int32_t tqHandlePutCommitted(TqMetaStore*, int64_t key, void* value);
+static void*   tqHandleGetUncommitted(TqMetaStore*, int64_t key);
+
+static inline void tqLinkUnpersist(TqMetaStore *pMeta, TqMetaList* pNode) {
+    if(pNode->unpersistNext == NULL) {
+      pNode->unpersistNext = pMeta->unpersistHead->unpersistNext;
+      pNode->unpersistPrev = pMeta->unpersistHead;
+      pMeta->unpersistHead->unpersistNext->unpersistPrev = pNode;
+      pMeta->unpersistHead->unpersistNext = pNode;
+    }
+}
+
 
 typedef struct TqMetaPageBuf {
   int16_t offset;
@@ -31,23 +42,34 @@ typedef struct TqMetaPageBuf {
 } TqMetaPageBuf;
 
 TqMetaStore* tqStoreOpen(const char* path,
-    int serializer(TqGroupHandle*, void**),
-    const void* deserializer(const void*, TqGroupHandle*),
-    void deleter(void*)) {
+    int serializer(const void* pObj, TqSerializedHead** ppHead),
+    const void* deserializer(const TqSerializedHead* pHead, void** ppObj),
+    void deleter(void* pObj)) {
   TqMetaStore* pMeta = malloc(sizeof(TqMetaStore)); 
   if(pMeta == NULL) {
     //close
     return NULL;
   }
+  memset(pMeta, 0, sizeof(TqMetaStore));
 
   //concat data file name and index file name
   size_t pathLen = strlen(path);
+  pMeta->dirPath = malloc(pathLen+1);
+  if(pMeta->dirPath != NULL) {
+    //TODO: memory insufficient
+  }
+  strcpy(pMeta->dirPath, path);
+  
   char name[pathLen+10];
 
   strcpy(name, path);
+  if(!taosDirExist(name) && !taosMkDir(name)) {
+    ASSERT(false);
+  }
   strcat(name, "/" TQ_IDX_NAME);
-  int idxFd = open(name, O_WRONLY | O_CREAT | O_EXCL, 0755);
+  int idxFd = open(name, O_RDWR | O_CREAT, 0755);
   if(idxFd < 0) {
+    ASSERT(false);
     //close file
     //free memory
     return NULL;
@@ -56,17 +78,24 @@ TqMetaStore* tqStoreOpen(const char* path,
   pMeta->idxFd = idxFd;
   pMeta->unpersistHead = malloc(sizeof(TqMetaList));
   if(pMeta->unpersistHead == NULL) {
+    ASSERT(false);
     //close file
     //free memory
     return NULL;
   }
+  memset(pMeta->unpersistHead, 0, sizeof(TqMetaList));
+  pMeta->unpersistHead->unpersistNext
+    = pMeta->unpersistHead->unpersistPrev
+    = pMeta->unpersistHead;
 
   strcpy(name, path);
   strcat(name, "/" TQ_META_NAME);
-  int fileFd = open(name, O_WRONLY | O_CREAT | O_EXCL, 0755);
-  if(fileFd < 0) return NULL;
+  int fileFd = open(name, O_RDWR | O_CREAT, 0755);
+  if(fileFd < 0){
+    ASSERT(false);
+    return NULL;
+  }
 
-  memset(pMeta, 0, sizeof(TqMetaStore));
   pMeta->fileFd = fileFd;
   
   pMeta->serializer = serializer;
@@ -74,23 +103,103 @@ TqMetaStore* tqStoreOpen(const char* path,
   pMeta->deleter = deleter;
 
   //read idx file and load into memory
-  char readBuf[TQ_PAGE_SIZE];
-  int readSize;
-  while((readSize = read(idxFd, readBuf, TQ_PAGE_SIZE)) != -1) {
+  char idxBuf[TQ_PAGE_SIZE];
+  TqSerializedHead* serializedObj = malloc(TQ_PAGE_SIZE);
+  if(serializedObj == NULL) {
+    //TODO:memory insufficient
+  }
+  int idxRead;
+  int allocated = TQ_PAGE_SIZE;
+  while((idxRead = read(idxFd, idxBuf, TQ_PAGE_SIZE))) {
+    if(idxRead == -1) {
+      //TODO: handle error
+      ASSERT(false);
+    }
     //loop read every entry
-    for(int i = 0; i < readSize; i += TQ_IDX_ENTRY_SIZE) {
-      TqMetaList *pNode = malloc(sizeof(TqMetaHandle));
-      memset(pNode, 0, sizeof(TqMetaList));
+    for(int i = 0; i < idxRead; i += TQ_IDX_ENTRY_SIZE) {
+      TqMetaList *pNode = malloc(sizeof(TqMetaList));
       if(pNode == NULL) {
         //TODO: free memory and return error
       }
-      memcpy(&pNode->handle, &readBuf[i], TQ_IDX_ENTRY_SIZE);
+      memset(pNode, 0, sizeof(TqMetaList));
+      memcpy(&pNode->handle, &idxBuf[i], TQ_IDX_ENTRY_SIZE);
+      lseek(fileFd, pNode->handle.offset, SEEK_CUR);
+      if(allocated < pNode->handle.serializedSize) {
+        void *ptr = realloc(serializedObj, pNode->handle.serializedSize);
+        if(ptr == NULL) {
+          //TODO: memory insufficient
+        }
+        serializedObj = ptr;
+        allocated = pNode->handle.serializedSize;
+      }
+      serializedObj->ssize = pNode->handle.serializedSize;
+      if(read(fileFd, serializedObj, pNode->handle.serializedSize) != pNode->handle.serializedSize) {
+        //TODO: read error
+      }
+      if(serializedObj->action == TQ_ACTION_INUSE) {
+        if(serializedObj->ssize != sizeof(TqSerializedHead)) {
+          pMeta->deserializer(serializedObj, &pNode->handle.valueInUse);
+        } else {
+          pNode->handle.valueInUse = TQ_DELETE_TOKEN;
+        }
+      } else if(serializedObj->action == TQ_ACTION_INTXN) {
+        if(serializedObj->ssize != sizeof(TqSerializedHead)) {
+          pMeta->deserializer(serializedObj, &pNode->handle.valueInTxn);
+        } else {
+          pNode->handle.valueInTxn = TQ_DELETE_TOKEN;
+        }
+      } else if(serializedObj->action == TQ_ACTION_INUSE_CONT) {
+        if(serializedObj->ssize != sizeof(TqSerializedHead)) {
+          pMeta->deserializer(serializedObj, &pNode->handle.valueInUse);
+        } else {
+          pNode->handle.valueInUse = TQ_DELETE_TOKEN;
+        }
+        serializedObj = POINTER_SHIFT(serializedObj, serializedObj->ssize);
+        if(serializedObj->ssize != sizeof(TqSerializedHead)) {
+          pMeta->deserializer(serializedObj, &pNode->handle.valueInTxn);
+        } else {
+          pNode->handle.valueInTxn = TQ_DELETE_TOKEN;
+        }
+      } else {
+        ASSERT(0);
+      }
+
+      //put into list
       int bucketKey = pNode->handle.key & TQ_BUCKET_SIZE;
-      pNode->next = pMeta->bucket[bucketKey];
-      pMeta->bucket[bucketKey] = pNode;
+      TqMetaList* pBucketNode = pMeta->bucket[bucketKey];
+      if(pBucketNode == NULL) {
+        pMeta->bucket[bucketKey] = pNode;
+      } else if(pBucketNode->handle.key == pNode->handle.key) {
+        pNode->next = pBucketNode->next;
+        pMeta->bucket[bucketKey] = pNode;
+      } else {
+        while(pBucketNode->next &&
+            pBucketNode->next->handle.key == pNode->handle.key) {
+          pBucketNode = pBucketNode->next; 
+        }
+        if(pBucketNode->next) {
+          ASSERT(pBucketNode->next->handle.key == pNode->handle.key);
+          TqMetaList *pNodeTmp = pBucketNode->next;
+          pBucketNode->next = pNodeTmp->next;
+          pBucketNode = pNodeTmp;
+        } else {
+          pBucketNode = NULL;
+        }
+      }
+      if(pBucketNode) {
+        if(pBucketNode->handle.valueInUse
+            && pBucketNode->handle.valueInUse != TQ_DELETE_TOKEN) {
+          pMeta->deleter(pBucketNode->handle.valueInUse);
+        }
+        if(pBucketNode->handle.valueInTxn
+            && pBucketNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
+          pMeta->deleter(pBucketNode->handle.valueInTxn);
+        }
+        free(pBucketNode);
+      }
     }
   }
-
+  free(serializedObj);
   return pMeta;
 }
 
@@ -102,30 +211,54 @@ int32_t tqStoreClose(TqMetaStore* pMeta) {
   close(pMeta->idxFd);
   //free memory
   for(int i = 0; i < TQ_BUCKET_SIZE; i++) {
-    TqMetaList* node = pMeta->bucket[i];
-    pMeta->bucket[i] = NULL;
-    while(node) {
-      ASSERT(node->unpersistNext == NULL);
-      ASSERT(node->unpersistPrev == NULL);
-      if(node->handle.valueInTxn) {
-        pMeta->deleter(node->handle.valueInTxn);
+    TqMetaList* pNode = pMeta->bucket[i];
+    while(pNode) {
+      ASSERT(pNode->unpersistNext == NULL);
+      ASSERT(pNode->unpersistPrev == NULL);
+      if(pNode->handle.valueInTxn
+          && pNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
+        pMeta->deleter(pNode->handle.valueInTxn);
       }
-      if(node->handle.valueInUse) {
-        pMeta->deleter(node->handle.valueInUse);
+      if(pNode->handle.valueInUse
+          && pNode->handle.valueInUse != TQ_DELETE_TOKEN) {
+        pMeta->deleter(pNode->handle.valueInUse);
       }
-      TqMetaList* next = node->next;
-      free(node);
-      node = next;
+      TqMetaList* next = pNode->next;
+      free(pNode);
+      pNode = next;
     }
   }
+  free(pMeta->dirPath);
+  free(pMeta->unpersistHead);
   free(pMeta);
   return 0;
 }
 
 int32_t tqStoreDelete(TqMetaStore* pMeta) {
-  //close file
-  //delete file
+  close(pMeta->fileFd);
+  close(pMeta->idxFd);
   //free memory
+  for(int i = 0; i < TQ_BUCKET_SIZE; i++) {
+    TqMetaList* pNode = pMeta->bucket[i];
+    pMeta->bucket[i] = NULL;
+    while(pNode) {
+      if(pNode->handle.valueInTxn
+          && pNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
+        pMeta->deleter(pNode->handle.valueInTxn);
+      }
+      if(pNode->handle.valueInUse
+          && pNode->handle.valueInUse != TQ_DELETE_TOKEN) {
+        pMeta->deleter(pNode->handle.valueInUse);
+      }
+      TqMetaList* next = pNode->next;
+      free(pNode);
+      pNode = next;
+    }
+  }
+  free(pMeta->unpersistHead);
+  taosRemoveDir(pMeta->dirPath);
+  free(pMeta->dirPath);
+  free(pMeta);
   return 0;
 }
 
@@ -135,69 +268,89 @@ int32_t tqStorePersist(TqMetaStore* pMeta) {
   int64_t* bufPtr = (int64_t*)writeBuf;
   TqMetaList *pHead = pMeta->unpersistHead;
   TqMetaList *pNode = pHead->unpersistNext;
+  TqSerializedHead *pSHead = malloc(sizeof(TqSerializedHead));
+  if(pSHead == NULL) {
+    //TODO: memory error
+    return -1;
+  }
+  pSHead->ver = TQ_SVER;
+  pSHead->checksum = 0;
+  pSHead->ssize = sizeof(TqSerializedHead);
+  int allocatedSize = sizeof(TqSerializedHead);
+  int offset = lseek(pMeta->fileFd, 0, SEEK_CUR);
   while(pHead != pNode) {
-    if(pNode->handle.valueInUse == NULL) {
-      //put delete token in data file
-      uint32_t delete = TQ_ACTION_DELETE;
-      int nBytes = write(pMeta->fileFd, &delete, sizeof(uint32_t));
-      ASSERT(nBytes == sizeof(uint32_t));
+    int nBytes = 0;
 
-      //remove from list
-      int bucketKey = pNode->handle.key & TQ_BUCKET_SIZE;
-      TqMetaList* pBucketHead = pMeta->bucket[bucketKey];
-      if(pBucketHead == pNode) {
-        pMeta->bucket[bucketKey] = pBucketHead->next;
+    if(pNode->handle.valueInUse) {
+      if(pNode->handle.valueInTxn) {
+        pSHead->action = TQ_ACTION_INUSE_CONT;
       } else {
-        TqMetaList* pBucketNode = pBucketHead;
-        while(pBucketNode->next != NULL
-            && pBucketNode->next != pNode) {
-          pBucketNode = pBucketNode->next; 
-        }
-        if(pBucketNode->next != NULL) {
-          ASSERT(pBucketNode->next == pNode);
-          pBucketNode->next = pNode->next;
-          if(pNode->handle.valueInUse) {
-            pMeta->deleter(pNode->handle.valueInUse);
-          }
-          free(pNode);
-        }
+        pSHead->action = TQ_ACTION_INUSE;
       }
+
+      if(pNode->handle.valueInUse == TQ_DELETE_TOKEN) {
+        pSHead->ssize = sizeof(TqSerializedHead);
+      } else {
+        pMeta->serializer(pNode->handle.valueInUse, &pSHead);
+      }
+      nBytes = write(pMeta->fileFd, pSHead, pSHead->ssize);
+      ASSERT(nBytes == pSHead->ssize);
     }
-    //serialize
-    void* pBytes = NULL;
-    int sz = pMeta->serializer(pNode->handle.valueInUse, &pBytes);
-    ASSERT(pBytes != NULL);
-    //get current offset
-    //append data
-    int64_t offset = lseek(pMeta->fileFd, 0, SEEK_CUR);
-    int nBytes = write(pMeta->fileFd, pBytes, sz);
-    //TODO: handle error in tfile
-    ASSERT(nBytes == sz);
 
-    pNode->handle.offset = offset;
-    pNode->handle.serializedSize = sz;
+    if(pNode->handle.valueInTxn) {
+      pSHead->action = TQ_ACTION_INTXN;
+      if(pNode->handle.valueInTxn == TQ_DELETE_TOKEN) {
+        pSHead->ssize = sizeof(TqSerializedHead);
+      } else {
+        pMeta->serializer(pNode->handle.valueInTxn, &pSHead);
+      }
+      int nBytesTxn = write(pMeta->fileFd, pSHead, pSHead->ssize);
+      ASSERT(nBytesTxn == pSHead->ssize);
+      nBytes += nBytesTxn;
+    }
 
-    //write idx
+    //write idx file
     //TODO: endian check and convert
     *(bufPtr++) = pNode->handle.key;
     *(bufPtr++) = pNode->handle.offset;
-    *(bufPtr++) = (int64_t)sz;
+    *(bufPtr++) = (int64_t)nBytes;
     if((char*)(bufPtr + 3) > writeBuf + TQ_PAGE_SIZE) {
       nBytes = write(pMeta->idxFd, writeBuf, sizeof(writeBuf));
-      //TODO: handle error in tfile
+      //TODO: handle error with tfile
       ASSERT(nBytes == sizeof(writeBuf));
       memset(writeBuf, 0, TQ_PAGE_SIZE);
       bufPtr = (int64_t*)writeBuf;
     }
-
     //remove from unpersist list
     pHead->unpersistNext = pNode->unpersistNext;
     pHead->unpersistNext->unpersistPrev = pHead;
-
     pNode->unpersistPrev = pNode->unpersistNext = NULL;
     pNode = pHead->unpersistNext;
+
+    //remove from bucket
+    if(pNode->handle.valueInUse == TQ_DELETE_TOKEN &&
+        pNode->handle.valueInTxn == NULL
+        ) {
+      int bucketKey = pNode->handle.key & TQ_BUCKET_SIZE;
+      TqMetaList* pBucketHead = pMeta->bucket[bucketKey];
+      if(pBucketHead == pNode) {
+        pMeta->bucket[bucketKey] = pNode->next;
+      } else {
+        TqMetaList* pBucketNode = pBucketHead;
+        while(pBucketNode->next != NULL
+            && pBucketNode->next != pNode) {
+          pBucketNode = pBucketNode->next; 
+        }
+        //impossible for pBucket->next == NULL
+        ASSERT(pBucketNode->next == pNode);
+        pBucketNode->next = pNode->next;
+      }
+      free(pNode);
+    }
   }
+
   //write left bytes
+  free(pSHead);
   if((char*)bufPtr != writeBuf) {
     int used = (char*)bufPtr - writeBuf;
     int nBytes = write(pMeta->idxFd, writeBuf, used);
@@ -216,7 +369,10 @@ static int32_t tqHandlePutCommitted(TqMetaStore* pMeta, int64_t key, void* value
   while(pNode) {
     if(pNode->handle.key == key) {
       //TODO: think about thread safety
-      pMeta->deleter(pNode->handle.valueInUse);
+      if(pNode->handle.valueInUse
+          && pNode->handle.valueInUse != TQ_DELETE_TOKEN) {
+        pMeta->deleter(pNode->handle.valueInUse);
+      }
       //change pointer ownership
       pNode->handle.valueInUse = value;
       return 0;
@@ -240,13 +396,13 @@ static int32_t tqHandlePutCommitted(TqMetaStore* pMeta, int64_t key, void* value
   return 0;
 }
 
-TqMetaHandle* tqHandleGet(TqMetaStore* pMeta, int64_t key) {
+void* tqHandleGet(TqMetaStore* pMeta, int64_t key) {
   int64_t bucketKey = key & TQ_BUCKET_SIZE;
   TqMetaList* pNode = pMeta->bucket[bucketKey];
   while(pNode) {
     if(pNode->handle.key == key) {
       if(pNode->handle.valueInUse != NULL) {
-        return &pNode->handle;
+        return pNode->handle.valueInUse;
       } else {
         return NULL;
       }
@@ -257,15 +413,19 @@ TqMetaHandle* tqHandleGet(TqMetaStore* pMeta, int64_t key) {
   return NULL;
 }
 
-int32_t tqHandlePut(TqMetaStore* pMeta, int64_t key, void* value) {
+int32_t tqHandleMovePut(TqMetaStore* pMeta, int64_t key, void* value) {
   int64_t bucketKey = key & TQ_BUCKET_SIZE;
   TqMetaList* pNode = pMeta->bucket[bucketKey];
   while(pNode) {
     if(pNode->handle.key == key) {
       //TODO: think about thread safety
-      pMeta->deleter(pNode->handle.valueInTxn);
+      if(pNode->handle.valueInTxn
+          && pNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
+        pMeta->deleter(pNode->handle.valueInTxn);
+      }
       //change pointer ownership
       pNode->handle.valueInTxn = value;
+      tqLinkUnpersist(pMeta, pNode);
       return 0;
     } else {
       pNode = pNode->next;
@@ -279,16 +439,58 @@ int32_t tqHandlePut(TqMetaStore* pMeta, int64_t key, void* value) {
   memset(pNewNode, 0, sizeof(TqMetaList));
   pNewNode->handle.key = key;
   pNewNode->handle.valueInTxn = value;
+  pNewNode->next = pMeta->bucket[bucketKey];
+  pMeta->bucket[bucketKey] = pNewNode;
+  tqLinkUnpersist(pMeta, pNewNode);
   return 0;
 }
 
-static TqMetaHandle* tqHandleGetUncommitted(TqMetaStore* pMeta, int64_t key) {
+int32_t tqHandleCopyPut(TqMetaStore* pMeta, int64_t key, void* value, size_t vsize) {
+  void *vmem = malloc(vsize);
+  if(vmem == NULL) {
+    //TODO: memory error
+    return -1;
+  }
+  memcpy(vmem, value, vsize);
   int64_t bucketKey = key & TQ_BUCKET_SIZE;
   TqMetaList* pNode = pMeta->bucket[bucketKey];
   while(pNode) {
     if(pNode->handle.key == key) {
-      if(pNode->handle.valueInTxn != NULL) {
-        return &pNode->handle;
+      //TODO: think about thread safety
+      if(pNode->handle.valueInTxn
+          && pNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
+        pMeta->deleter(pNode->handle.valueInTxn);
+      }
+      //change pointer ownership
+      pNode->handle.valueInTxn = vmem;
+      tqLinkUnpersist(pMeta, pNode);
+      return 0;
+    } else {
+      pNode = pNode->next;
+    }
+  }
+  TqMetaList *pNewNode = malloc(sizeof(TqMetaList));
+  if(pNewNode == NULL) {
+    //TODO: memory error
+    return -1;
+  }
+  memset(pNewNode, 0, sizeof(TqMetaList));
+  pNewNode->handle.key = key;
+  pNewNode->handle.valueInTxn = vmem;
+  pNewNode->next = pMeta->bucket[bucketKey];
+  pMeta->bucket[bucketKey] = pNewNode;
+  tqLinkUnpersist(pMeta, pNewNode);
+  return 0;
+}
+
+static void* tqHandleGetUncommitted(TqMetaStore* pMeta, int64_t key) {
+  int64_t bucketKey = key & TQ_BUCKET_SIZE;
+  TqMetaList* pNode = pMeta->bucket[bucketKey];
+  while(pNode) {
+    if(pNode->handle.key == key) {
+      if(pNode->handle.valueInTxn != NULL
+          && pNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
+        return pNode->handle.valueInTxn;
       } else {
         return NULL;
       }
@@ -304,16 +506,13 @@ int32_t tqHandleCommit(TqMetaStore* pMeta, int64_t key) {
   TqMetaList* pNode = pMeta->bucket[bucketKey];
   while(pNode) {
     if(pNode->handle.key == key) {
-      if(pNode->handle.valueInUse != NULL) {
+      if(pNode->handle.valueInUse
+          && pNode->handle.valueInUse != TQ_DELETE_TOKEN) {
         pMeta->deleter(pNode->handle.valueInUse);
       }
       pNode->handle.valueInUse = pNode->handle.valueInTxn;
-      if(pNode->unpersistNext == NULL) {
-        pNode->unpersistNext = pMeta->unpersistHead->unpersistNext;
-        pNode->unpersistPrev = pMeta->unpersistHead;
-        pMeta->unpersistHead->unpersistNext->unpersistPrev = pNode;
-        pMeta->unpersistHead->unpersistNext = pNode;
-      }
+      pNode->handle.valueInTxn = NULL;
+      tqLinkUnpersist(pMeta, pNode);
       return 0;
     } else {
       pNode = pNode->next;
@@ -327,9 +526,12 @@ int32_t tqHandleAbort(TqMetaStore* pMeta, int64_t key) {
   TqMetaList* pNode = pMeta->bucket[bucketKey];
   while(pNode) {
     if(pNode->handle.key == key) {
-      if(pNode->handle.valueInTxn != NULL) {
-        pMeta->deleter(pNode->handle.valueInTxn);
+      if(pNode->handle.valueInTxn) {
+        if(pNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
+          pMeta->deleter(pNode->handle.valueInTxn);
+        }
         pNode->handle.valueInTxn = NULL;
+        tqLinkUnpersist(pMeta, pNode);
         return 0;
       }
       return -1;
@@ -344,9 +546,11 @@ int32_t tqHandleDel(TqMetaStore* pMeta, int64_t key) {
   int64_t bucketKey = key & TQ_BUCKET_SIZE;
   TqMetaList* pNode = pMeta->bucket[bucketKey];
   while(pNode) {
-    if(pNode->handle.key == key) {
+      if(pNode->handle.valueInTxn
+          && pNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
       pMeta->deleter(pNode->handle.valueInTxn);
-      pNode->handle.valueInTxn = NULL;
+      pNode->handle.valueInTxn = TQ_DELETE_TOKEN;
+      tqLinkUnpersist(pMeta, pNode);
       return 0;
     } else {
       pNode = pNode->next;
@@ -364,21 +568,20 @@ int32_t tqHandleClear(TqMetaStore* pMeta, int64_t key) {
     if(pNode->handle.key == key) {
       if(pNode->handle.valueInUse != NULL) {
         exist = true;
-        pMeta->deleter(pNode->handle.valueInUse);
-        pNode->handle.valueInUse = NULL;
+        if(pNode->handle.valueInUse != TQ_DELETE_TOKEN) {
+          pMeta->deleter(pNode->handle.valueInUse);
+        }
+        pNode->handle.valueInUse = TQ_DELETE_TOKEN;
       }
       if(pNode->handle.valueInTxn != NULL) {
         exist = true;
-        pMeta->deleter(pNode->handle.valueInTxn);
-        pNode->handle.valueInTxn = NULL;
+        if(pNode->handle.valueInTxn != TQ_DELETE_TOKEN) {
+          pMeta->deleter(pNode->handle.valueInTxn);
+        }
+        pNode->handle.valueInTxn = TQ_DELETE_TOKEN;
       }
       if(exist) {
-        if(pNode->unpersistNext == NULL) {
-          pNode->unpersistNext = pMeta->unpersistHead->unpersistNext;
-          pNode->unpersistPrev = pMeta->unpersistHead;
-          pMeta->unpersistHead->unpersistNext->unpersistPrev = pNode;
-          pMeta->unpersistHead->unpersistNext = pNode;
-        }
+        tqLinkUnpersist(pMeta, pNode);
         return 0;
       }
       return -1;
diff --git a/source/dnode/vnode/tq/test/CMakeLists.txt b/source/dnode/vnode/tq/test/CMakeLists.txt
new file mode 100644
index 0000000000000000000000000000000000000000..6b468497d57754f20dca2392d79cb5933b969b76
--- /dev/null
+++ b/source/dnode/vnode/tq/test/CMakeLists.txt
@@ -0,0 +1,20 @@
+add_executable(tqTest "")
+target_sources(tqTest
+    PRIVATE
+    "tqMetaTest.cpp"
+)
+target_include_directories(tqTest
+    PUBLIC
+    "${CMAKE_SOURCE_DIR}/include/server/vnode/tq"
+    "${CMAKE_CURRENT_SOURCE_DIR}/../inc"
+)
+
+target_link_libraries(tqTest
+    tq
+    gtest_main
+)
+enable_testing()
+add_test(
+    NAME tq_test
+    COMMAND tqTest
+)
diff --git a/source/dnode/vnode/tq/test/tqMetaTest.cpp b/source/dnode/vnode/tq/test/tqMetaTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..20a0368c4c27a9a983a7553ec0ae6bae050717ac
--- /dev/null
+++ b/source/dnode/vnode/tq/test/tqMetaTest.cpp
@@ -0,0 +1,133 @@
+#include <gtest/gtest.h>
+#include <cstring>
+#include <iostream>
+#include <queue>
+
+#include "tqMetaStore.h"
+
+struct Foo {
+  int32_t a;
+};
+
+int FooSerializer(const void* pObj, TqSerializedHead** ppHead) {
+  Foo* foo = (Foo*) pObj;
+  if((*ppHead) == NULL || (*ppHead)->ssize < sizeof(TqSerializedHead) + sizeof(int32_t)) {
+    *ppHead = (TqSerializedHead*)realloc(*ppHead, sizeof(TqSerializedHead) + sizeof(int32_t));
+    (*ppHead)->ssize = sizeof(TqSerializedHead) + sizeof(int32_t);
+  }
+  *(int32_t*)(*ppHead)->content = foo->a;
+  return (*ppHead)->ssize;
+}
+
+const void* FooDeserializer(const TqSerializedHead* pHead, void** ppObj) {
+  if(*ppObj == NULL) {
+    *ppObj = realloc(*ppObj, sizeof(int32_t));
+  }
+  Foo* pFoo = *(Foo**)ppObj;
+  pFoo->a = *(int32_t*)pHead->content; 
+  return NULL;
+}
+
+void FooDeleter(void* pObj) {
+  free(pObj); 
+}
+
+class TqMetaTest : public ::testing::Test {
+  protected:
+
+    void SetUp() override {
+      taosRemoveDir(pathName);
+      pMeta = tqStoreOpen(pathName,
+          FooSerializer, FooDeserializer, FooDeleter);
+      ASSERT(pMeta);
+    }
+
+    void TearDown() override {
+      tqStoreClose(pMeta);
+    }
+
+    TqMetaStore* pMeta;
+    const char* pathName = "/tmp/tq_test";
+};
+
+TEST_F(TqMetaTest, copyPutTest) {
+  Foo foo;
+  foo.a = 3;
+  tqHandleCopyPut(pMeta, 1, &foo, sizeof(Foo));
+
+  Foo* pFoo = (Foo*) tqHandleGet(pMeta, 1);
+  EXPECT_EQ(pFoo == NULL, true);
+}
+
+TEST_F(TqMetaTest, persistTest) {
+  Foo* pFoo = (Foo*)malloc(sizeof(Foo));
+  pFoo->a = 2;
+  tqHandleMovePut(pMeta, 1, pFoo);
+  Foo* pBar = (Foo*)tqHandleGet(pMeta, 1);
+  EXPECT_EQ(pBar == NULL, true);
+  tqHandleCommit(pMeta, 1);
+  pBar = (Foo*)tqHandleGet(pMeta, 1);
+  EXPECT_EQ(pBar->a, pFoo->a);
+  pBar = (Foo*)tqHandleGet(pMeta, 2);
+  EXPECT_EQ(pBar == NULL, true);
+
+  tqStoreClose(pMeta);
+  pMeta = tqStoreOpen(pathName,
+      FooSerializer, FooDeserializer, FooDeleter);
+  ASSERT(pMeta);
+
+  pBar = (Foo*)tqHandleGet(pMeta, 1);
+  ASSERT_EQ(pBar != NULL, true);
+  EXPECT_EQ(pBar->a, 2);
+
+  pBar = (Foo*)tqHandleGet(pMeta, 2);
+  EXPECT_EQ(pBar == NULL, true);
+
+  //taosRemoveDir(pathName);
+}
+
+TEST_F(TqMetaTest, uncommittedTest) {
+  Foo* pFoo = (Foo*)malloc(sizeof(Foo));
+  pFoo->a = 3;
+  tqHandleMovePut(pMeta, 1, pFoo);
+
+  pFoo = (Foo*) tqHandleGet(pMeta, 1);
+  EXPECT_EQ(pFoo == NULL, true);
+}
+
+TEST_F(TqMetaTest, abortTest) {
+  Foo* pFoo = (Foo*)malloc(sizeof(Foo));
+  pFoo->a = 3;
+  tqHandleMovePut(pMeta, 1, pFoo);
+
+  pFoo = (Foo*) tqHandleGet(pMeta, 1);
+  EXPECT_EQ(pFoo == NULL, true);
+
+  tqHandleAbort(pMeta, 1);
+  pFoo = (Foo*) tqHandleGet(pMeta, 1);
+  EXPECT_EQ(pFoo == NULL, true);
+}
+
+TEST_F(TqMetaTest, deleteTest) {
+  Foo* pFoo = (Foo*)malloc(sizeof(Foo));
+  pFoo->a = 3;
+  tqHandleMovePut(pMeta, 1, pFoo);
+
+  pFoo = (Foo*) tqHandleGet(pMeta, 1);
+  EXPECT_EQ(pFoo == NULL, true);
+
+  tqHandleCommit(pMeta, 1);
+
+  pFoo = (Foo*) tqHandleGet(pMeta, 1);
+  ASSERT_EQ(pFoo != NULL, true);
+  EXPECT_EQ(pFoo->a, 3);
+
+  tqHandleDel(pMeta, 1);
+  pFoo = (Foo*) tqHandleGet(pMeta, 1);
+  ASSERT_EQ(pFoo != NULL, true);
+  EXPECT_EQ(pFoo->a, 3);
+
+  tqHandleCommit(pMeta, 1);
+  pFoo = (Foo*) tqHandleGet(pMeta, 1);
+  EXPECT_EQ(pFoo == NULL, true);
+}
diff --git a/source/dnode/vnode/tq/test/tqTests.cpp b/source/dnode/vnode/tq/test/tqTests.cpp
deleted file mode 100644
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..0000000000000000000000000000000000000000
diff --git a/source/os/src/osDir.c b/source/os/src/osDir.c
index 17ab88edf64c3e8139d392f8dcb244c15543e93c..3b3e04378f73c76f2e85da2dc3f7788f3b49cdc5 100644
--- a/source/os/src/osDir.c
+++ b/source/os/src/osDir.c
@@ -55,7 +55,7 @@ void taosRemoveDir(const char *dirname) {
   closedir(dir);
   rmdir(dirname);
 
-  printf("dir:%s is removed", dirname);
+  printf("dir:%s is removed\n", dirname);
 }
 
 bool taosDirExist(char *dirname) { return access(dirname, F_OK) == 0; }
@@ -138,4 +138,4 @@ bool taosRealPath(char *dirname, int32_t maxlen) {
   return true;
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/source/util/src/terror.c b/source/util/src/terror.c
index 6838bab403cf63bd4287adcc791c56e95de08bb9..324f78ad793b2aa9f92b4a4dd309960c71c9180d 100644
--- a/source/util/src/terror.c
+++ b/source/util/src/terror.c
@@ -228,14 +228,18 @@ TAOS_DEFINE_ERROR(TSDB_CODE_MND_TOPIC_ALREADY_EXIST,      "Topic already exists"
 // dnode
 TAOS_DEFINE_ERROR(TSDB_CODE_DND_MSG_NOT_PROCESSED,        "Message not processed")
 TAOS_DEFINE_ERROR(TSDB_CODE_DND_OUT_OF_MEMORY,            "Dnode out of memory")
-TAOS_DEFINE_ERROR(TSDB_CODE_DND_DNODE_ID_NOT_MATCHED,     "Dnode Id not matched")
-TAOS_DEFINE_ERROR(TSDB_CODE_DND_MNODE_ALREADY_DROPPED,    "Mnode already deployed")
+TAOS_DEFINE_ERROR(TSDB_CODE_DND_MNODE_ID_NOT_MATCH_DNODE, "Mnode Id not match Dnode")
+TAOS_DEFINE_ERROR(TSDB_CODE_DND_MNODE_ALREADY_DEPLOYED,   "Mnode already deployed")
+TAOS_DEFINE_ERROR(TSDB_CODE_DND_MNODE_NOT_DEPLOYED,       "Mnode not deployed")
+TAOS_DEFINE_ERROR(TSDB_CODE_DND_READ_MNODE_FILE_ERROR,    "Read mnode.json error")
+TAOS_DEFINE_ERROR(TSDB_CODE_DND_WRITE_MNODE_FILE_ERROR,   "Write mnode.json error")
 TAOS_DEFINE_ERROR(TSDB_CODE_DND_NO_WRITE_ACCESS,          "No permission for disk files in dnode")
 TAOS_DEFINE_ERROR(TSDB_CODE_DND_INVALID_MSG_LEN,          "Invalid message length")
 TAOS_DEFINE_ERROR(TSDB_CODE_DND_ACTION_IN_PROGRESS,       "Action in progress")
 TAOS_DEFINE_ERROR(TSDB_CODE_DND_TOO_MANY_VNODES,          "Too many vnode directories")
 TAOS_DEFINE_ERROR(TSDB_CODE_DND_EXITING,                  "Dnode is exiting")
 TAOS_DEFINE_ERROR(TSDB_CODE_DND_PARSE_VNODE_FILE_ERROR,   "Parse vnodes.json error")
+TAOS_DEFINE_ERROR(TSDB_CODE_DND_PARSE_DNODE_FILE_ERROR,   "Parse dnodes.json error")
 
 // vnode
 TAOS_DEFINE_ERROR(TSDB_CODE_VND_ACTION_IN_PROGRESS,       "Action in progress")