diff --git a/source/dnode/vnode/src/tsdb/dev/inc/tsdbFS.h b/source/dnode/vnode/src/tsdb/dev/inc/tsdbFS.h
index 8d51b6a16e..093ed39a99 100644
--- a/source/dnode/vnode/src/tsdb/dev/inc/tsdbFS.h
+++ b/source/dnode/vnode/src/tsdb/dev/inc/tsdbFS.h
@@ -39,7 +39,7 @@ int32_t tsdbCloseFS(STFileSystem **fs);
 int32_t tsdbFSCreateCopySnapshot(STFileSystem *fs, TFileSetArray **fsetArr);
 int32_t tsdbFSDestroyCopySnapshot(TFileSetArray **fsetArr);
 // txn
-int32_t tsdbFSAllocEid(STFileSystem *fs, int64_t *eid);
+int64_t tsdbFSAllocEid(STFileSystem *fs);
 int32_t tsdbFSEditBegin(STFileSystem *fs, const TFileOpArray *opArray, EFEditT etype);
 int32_t tsdbFSEditCommit(STFileSystem *fs);
 int32_t tsdbFSEditAbort(STFileSystem *fs);
diff --git a/source/dnode/vnode/src/tsdb/dev/inc/tsdbFSet.h b/source/dnode/vnode/src/tsdb/dev/inc/tsdbFSet.h
index acb83deece..a0811d8207 100644
--- a/source/dnode/vnode/src/tsdb/dev/inc/tsdbFSet.h
+++ b/source/dnode/vnode/src/tsdb/dev/inc/tsdbFSet.h
@@ -52,7 +52,7 @@ int32_t tsdbTFileSetApplyEdit(STsdb *pTsdb, const STFileSet *fset1, STFileSet *f
 // max commit id
 int64_t tsdbTFileSetMaxCid(const STFileSet *fset);
 // get
-SSttLvl *tsdbTFileSetGetLvl(STFileSet *fset, int32_t level);
+SSttLvl *tsdbTFileSetGetSttLvl(STFileSet *fset, int32_t level);
 // is empty
 bool tsdbTFileSetIsEmpty(const STFileSet *fset);
 
diff --git a/source/dnode/vnode/src/tsdb/dev/inc/tsdbIter.h b/source/dnode/vnode/src/tsdb/dev/inc/tsdbIter.h
index 6e17c386b6..e3b3d45ba1 100644
--- a/source/dnode/vnode/src/tsdb/dev/inc/tsdbIter.h
+++ b/source/dnode/vnode/src/tsdb/dev/inc/tsdbIter.h
@@ -53,8 +53,8 @@ int32_t tsdbIterClose(STsdbIter **iter);
 int32_t tsdbIterNext(STsdbIter *iter);
 
 // SIterMerger ===============
-int32_t   tsdbIterMergerInit(const TTsdbIterArray *iterArray, SIterMerger **merger);
-int32_t   tsdbIterMergerClear(SIterMerger **merger);
+int32_t   tsdbIterMergerOpen(const TTsdbIterArray *iterArray, SIterMerger **merger);
+int32_t   tsdbIterMergerClose(SIterMerger **merger);
 int32_t   tsdbIterMergerNext(SIterMerger *merger);
 SRowInfo *tsdbIterMergerGet(SIterMerger *merger);
 int32_t   tsdbIterMergerSkipTableData(SIterMerger *merger, const TABLEID *tbid);
diff --git a/source/dnode/vnode/src/tsdb/dev/inc/tsdbSttFileRW.h b/source/dnode/vnode/src/tsdb/dev/inc/tsdbSttFileRW.h
index d104af5875..594aca9a67 100644
--- a/source/dnode/vnode/src/tsdb/dev/inc/tsdbSttFileRW.h
+++ b/source/dnode/vnode/src/tsdb/dev/inc/tsdbSttFileRW.h
@@ -52,8 +52,6 @@ struct SSttFileReaderConfig {
   STsdb    *tsdb;
   int32_t   szPage;
   STFile    file[1];
-  SSkmInfo *skmTb;
-  SSkmInfo *skmRow;
   uint8_t **bufArr;
 };
 
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbCommit.c b/source/dnode/vnode/src/tsdb/dev/tsdbCommit.c
index 4de9337eb8..8bb034c265 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbCommit.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbCommit.c
@@ -17,16 +17,20 @@
 
 // extern dependencies
 typedef struct {
-  STsdb  *tsdb;
+  STsdb         *tsdb;
+  TFileSetArray *fsetArr;
+
   int32_t minutes;
   int8_t  precision;
   int32_t minRow;
   int32_t maxRow;
   int8_t  cmprAlg;
-  int8_t  sttTrigger;
+  int32_t sttTrigger;
+  int32_t szPage;
   int64_t compactVersion;
 
   struct {
+    int64_t    cid;
     int64_t    now;
     TSKEY      nextKey;
     int32_t    fid;
@@ -37,111 +41,115 @@ typedef struct {
     TABLEID    tbid[1];
   } ctx[1];
 
-  int64_t        eid;  // edit id
   TFileOpArray   fopArray[1];
   TTsdbIterArray iterArray[1];
   SIterMerger   *iterMerger;
 
   // writer
-  SDataFileWriter *dataWriter;
   SSttFileWriter  *sttWriter;
+  SDataFileWriter *dataWriter;
 } SCommitter2;
 
-static int32_t tsdbCommitOpenNewSttWriter(SCommitter2 *pCommitter) {
+static int32_t tsdbCommitOpenNewSttWriter(SCommitter2 *committer) {
   int32_t code = 0;
   int32_t lino = 0;
-  STsdb  *pTsdb = pCommitter->tsdb;
-  SVnode *pVnode = pTsdb->pVnode;
-  int32_t vid = TD_VID(pVnode);
 
-  SSttFileWriterConfig config[1];
-  SDiskID              did[1];
-
-  if (tfsAllocDisk(pVnode->pTfs, pCommitter->ctx->expLevel, did) < 0) {
+  SDiskID did[1];
+  if (tfsAllocDisk(committer->tsdb->pVnode->pTfs, committer->ctx->expLevel, did) < 0) {
     code = TSDB_CODE_FS_NO_VALID_DISK;
     TSDB_CHECK_CODE(code, lino, _exit);
   }
 
-  config->tsdb = pTsdb;
-  config->maxRow = pCommitter->maxRow;
-  config->szPage = pVnode->config.tsdbPageSize;
-  config->cmprAlg = pCommitter->cmprAlg;
-  config->skmTb = NULL;
-  config->skmRow = NULL;
-  config->aBuf = NULL;
-  config->file.type = TSDB_FTYPE_STT;
-  config->file.did = did[0];
-  config->file.fid = pCommitter->ctx->fid;
-  config->file.cid = pCommitter->eid;
-  config->file.size = 0;
-  config->file.stt->level = 0;
-  config->file.stt->nseg = 0;
+  SSttFileWriterConfig config[1] = {{
+      .tsdb = committer->tsdb,
+      .maxRow = committer->maxRow,
+      .szPage = committer->tsdb->pVnode->config.tsdbPageSize,
+      .cmprAlg = committer->cmprAlg,
+      .compactVersion = committer->compactVersion,
+      .file =
+          {
+              .type = TSDB_FTYPE_STT,
+              .did = did[0],
+              .fid = committer->ctx->fid,
+              .cid = committer->ctx->cid,
+          },
+  }};
 
-  code = tsdbSttFileWriterOpen(config, &pCommitter->sttWriter);
+  code = tsdbSttFileWriterOpen(config, &committer->sttWriter);
   TSDB_CHECK_CODE(code, lino, _exit);
 
 _exit:
   if (code) {
-    tsdbError("vgId:%d %s failed at line %d since %s", vid, __func__, lino, tstrerror(code));
+    TSDB_ERROR_LOG(TD_VID(committer->tsdb->pVnode), lino, code);
   } else {
-    tsdbDebug("vgId:%d %s success", vid, __func__);
+    tsdbDebug("vgId:%d %s success", TD_VID(committer->tsdb->pVnode), __func__);
   }
   return code;
 }
-static int32_t tsdbCommitOpenExistSttWriter(SCommitter2 *pCommitter, const STFile *pFile) {
+
+static int32_t tsdbCommitOpenExistSttWriter(SCommitter2 *committer, const STFile *f) {
   int32_t code = 0;
   int32_t lino = 0;
-  STsdb  *pTsdb = pCommitter->tsdb;
-  SVnode *pVnode = pTsdb->pVnode;
-  int32_t vid = TD_VID(pVnode);
 
-  SSttFileWriterConfig config = {
-      //
-      .tsdb = pTsdb,
-      .maxRow = pCommitter->maxRow,
-      .szPage = pVnode->config.tsdbPageSize,
-      .cmprAlg = pCommitter->cmprAlg,
-      .skmTb = NULL,
-      .skmRow = NULL,
-      .aBuf = NULL,
-      .file = *pFile  //
-  };
+  SSttFileWriterConfig config[1] = {{
+      .tsdb = committer->tsdb,
+      .maxRow = committer->maxRow,
+      .szPage = committer->szPage,
+      .cmprAlg = committer->cmprAlg,
+      .compactVersion = committer->compactVersion,
+      .file = f[0],
+  }};
 
-  code = tsdbSttFileWriterOpen(&config, &pCommitter->sttWriter);
+  code = tsdbSttFileWriterOpen(config, &committer->sttWriter);
   TSDB_CHECK_CODE(code, lino, _exit);
 
 _exit:
   if (code) {
-    tsdbError("vgId:%d %s failed at line %d since %s", vid, __func__, lino, tstrerror(code));
+    TSDB_ERROR_LOG(TD_VID(committer->tsdb->pVnode), lino, code);
   } else {
-    tsdbDebug("vgId:%d %s success", vid, __func__);
+    tsdbDebug("vgId:%d %s success", TD_VID(committer->tsdb->pVnode), __func__);
   }
   return code;
 }
+
 static int32_t tsdbCommitOpenWriter(SCommitter2 *committer) {
+  int32_t code = 0;
+  int32_t lino = 0;
+
+  // stt writer
   if (!committer->ctx->fset) {
-    return tsdbCommitOpenNewSttWriter(committer);
+    code = tsdbCommitOpenNewSttWriter(committer);
+    TSDB_CHECK_CODE(code, lino, _exit);
   }
 
-  const SSttLvl *lvl0 = tsdbTFileSetGetLvl(committer->ctx->fset, 0);
-  if (lvl0 == NULL) {
-    return tsdbCommitOpenNewSttWriter(committer);
+  const SSttLvl *lvl0 = tsdbTFileSetGetSttLvl(committer->ctx->fset, 0);
+  if (lvl0 == NULL || TARRAY2_SIZE(lvl0->fobjArr) == 0) {
+    code = tsdbCommitOpenNewSttWriter(committer);
+    TSDB_CHECK_CODE(code, lino, _exit);
   }
 
-  ASSERT(TARRAY2_SIZE(lvl0->fobjArr) > 0);
   STFileObj *fobj = TARRAY2_LAST(lvl0->fobjArr);
   if (fobj->f->stt->nseg >= committer->sttTrigger) {
-    return tsdbCommitOpenNewSttWriter(committer);
+    code = tsdbCommitOpenNewSttWriter(committer);
+    TSDB_CHECK_CODE(code, lino, _exit);
   } else {
-    return tsdbCommitOpenExistSttWriter(committer, fobj->f);
+    code = tsdbCommitOpenExistSttWriter(committer, fobj->f);
+    TSDB_CHECK_CODE(code, lino, _exit);
   }
+
+  // data writer
+  if (0) {
+    // TODO
+  }
+
+_exit:
+  if (code) {
+    TSDB_ERROR_LOG(TD_VID(committer->tsdb->pVnode), lino, code);
+  }
+  return code;
 }
 
-static int32_t tsdbCommitTSRow(SCommitter2 *committer, SRowInfo *row) {
-  return tsdbSttFileWriteTSData(committer->sttWriter, row);
-}
-
-static int32_t tsdbCommitWriteDelData(SCommitter2 *pCommitter, int64_t suid, int64_t uid, int64_t version, int64_t sKey,
+static int32_t tsdbCommitWriteDelData(SCommitter2 *committer, int64_t suid, int64_t uid, int64_t version, int64_t sKey,
                                       int64_t eKey) {
   int32_t code = 0;
   // TODO
@@ -174,7 +182,7 @@ static int32_t tsdbCommitTSData(SCommitter2 *committer) {
   code = TARRAY2_APPEND(committer->iterArray, iter);
   TSDB_CHECK_CODE(code, lino, _exit);
 
-  code = tsdbIterMergerInit(committer->iterArray, &committer->iterMerger);
+  code = tsdbIterMergerOpen(committer->iterArray, &committer->iterMerger);
   TSDB_CHECK_CODE(code, lino, _exit);
 
   // loop iter
@@ -183,7 +191,7 @@ static int32_t tsdbCommitTSData(SCommitter2 *committer) {
       committer->ctx->tbid->suid = row->suid;
       committer->ctx->tbid->uid = row->uid;
 
-      // Ignore deleted table
+      // Ignore table of obsolescence
       SMetaInfo info[1];
       if (metaGetInfo(committer->tsdb->pVnode->pMeta, row->uid, info, NULL) != 0) {
         code = tsdbIterMergerSkipTableData(committer->iterMerger, committer->ctx->tbid);
@@ -195,11 +203,10 @@ static int32_t tsdbCommitTSData(SCommitter2 *committer) {
     TSKEY ts = TSDBROW_TS(&row->row);
     if (ts > committer->ctx->maxKey) {
       committer->ctx->nextKey = TMIN(committer->ctx->nextKey, ts);
-
       code = tsdbIterMergerSkipTableData(committer->iterMerger, committer->ctx->tbid);
       TSDB_CHECK_CODE(code, lino, _exit);
     } else {
-      code = tsdbCommitTSRow(committer, row);
+      code = tsdbSttFileWriteTSData(committer->sttWriter, row);
       TSDB_CHECK_CODE(code, lino, _exit);
 
       code = tsdbIterMergerNext(committer->iterMerger);
@@ -216,7 +223,7 @@ _exit:
   return code;
 }
 
-static int32_t tsdbCommitDelData(SCommitter2 *pCommitter) {
+static int32_t tsdbCommitDelData(SCommitter2 *committer) {
   int32_t code = 0;
   int32_t lino;
 
@@ -226,23 +233,23 @@ static int32_t tsdbCommitDelData(SCommitter2 *pCommitter) {
   ASSERTS(0, "TODO: Not implemented yet");
 
   int64_t    nDel = 0;
-  SMemTable *pMem = pCommitter->tsdb->imem;
+  SMemTable *pMem = committer->tsdb->imem;
 
   if (pMem->nDel == 0) {  // no del data
     goto _exit;
   }
 
-  for (int32_t iTbData = 0; iTbData < taosArrayGetSize(pCommitter->aTbDataP); iTbData++) {
-    STbData *pTbData = (STbData *)taosArrayGetP(pCommitter->aTbDataP, iTbData);
+  for (int32_t iTbData = 0; iTbData < taosArrayGetSize(committer->aTbDataP); iTbData++) {
+    STbData *pTbData = (STbData *)taosArrayGetP(committer->aTbDataP, iTbData);
 
     for (SDelData *pDelData = pTbData->pHead; pDelData; pDelData = pDelData->pNext) {
-      if (pDelData->eKey < pCommitter->ctx->minKey) continue;
-      if (pDelData->sKey > pCommitter->ctx->maxKey) {
-        pCommitter->ctx->nextKey = TMIN(pCommitter->ctx->nextKey, pDelData->sKey);
+      if (pDelData->eKey < committer->ctx->minKey) continue;
+      if (pDelData->sKey > committer->ctx->maxKey) {
+        committer->ctx->nextKey = TMIN(committer->ctx->nextKey, pDelData->sKey);
         continue;
       }
 
-      code = tsdbCommitWriteDelData(pCommitter, pTbData->suid, pTbData->uid, pDelData->version,
+      code = tsdbCommitWriteDelData(committer, pTbData->suid, pTbData->uid, pDelData->version,
                                     pDelData->sKey /* TODO */, pDelData->eKey /* TODO */);
       TSDB_CHECK_CODE(code, lino, _exit);
     }
@@ -250,9 +257,9 @@ static int32_t tsdbCommitDelData(SCommitter2 *pCommitter) {
 
 _exit:
   if (code) {
-    tsdbError("vgId:%d failed at line %d since %s", TD_VID(pCommitter->tsdb->pVnode), lino, tstrerror(code));
+    tsdbError("vgId:%d failed at line %d since %s", TD_VID(committer->tsdb->pVnode), lino, tstrerror(code));
   } else {
-    tsdbDebug("vgId:%d %s done, fid:%d nDel:%" PRId64, TD_VID(pCommitter->tsdb->pVnode), __func__, pCommitter->ctx->fid,
+    tsdbDebug("vgId:%d %s done, fid:%d nDel:%" PRId64, TD_VID(committer->tsdb->pVnode), __func__, committer->ctx->fid,
               pMem->nDel);
   }
   return code;
@@ -266,17 +273,26 @@ static int32_t tsdbCommitFileSetBegin(SCommitter2 *committer) {
   int32_t vid = TD_VID(tsdb->pVnode);
 
   committer->ctx->fid = tsdbKeyFid(committer->ctx->nextKey, committer->minutes, committer->precision);
+  committer->ctx->expLevel = tsdbFidLevel(committer->ctx->fid, &tsdb->keepCfg, committer->ctx->now);
   tsdbFidKeyRange(committer->ctx->fid, committer->minutes, committer->precision, &committer->ctx->minKey,
                   &committer->ctx->maxKey);
-  committer->ctx->expLevel = tsdbFidLevel(committer->ctx->fid, &tsdb->keepCfg, committer->ctx->now);
-  committer->ctx->nextKey = TSKEY_MAX;
+  STFileSet fset = {.fid = committer->ctx->fid};
+  committer->ctx->fset = &fset;
+  committer->ctx->fset = TARRAY2_SEARCH_EX(committer->fsetArr, &committer->ctx->fset, tsdbTFileSetCmprFn, TD_EQ);
+  committer->ctx->tbid->suid = 0;
+  committer->ctx->tbid->uid = 0;
 
-  // TODO: use a thread safe function to get fset
-  tsdbFSGetFSet(tsdb->pFS, committer->ctx->fid, &committer->ctx->fset);
+  ASSERT(TARRAY2_SIZE(committer->iterArray) == 0);
+  ASSERT(committer->iterMerger == NULL);
+  ASSERT(committer->sttWriter == NULL);
+  ASSERT(committer->dataWriter == NULL);
 
   code = tsdbCommitOpenWriter(committer);
   TSDB_CHECK_CODE(code, lino, _exit);
 
+  // reset nextKey
+  committer->ctx->nextKey = TSKEY_MAX;
+
 _exit:
   if (code) {
     TSDB_ERROR_LOG(vid, lino, code);
@@ -287,27 +303,27 @@ _exit:
   return 0;
 }
 
-static int32_t tsdbCommitFileSetEnd(SCommitter2 *pCommitter) {
+static int32_t tsdbCommitFileSetEnd(SCommitter2 *committer) {
   int32_t code = 0;
   int32_t lino = 0;
-  int32_t vid = TD_VID(pCommitter->tsdb->pVnode);
 
-  if (pCommitter->sttWriter == NULL) return 0;
-
-  STFileOp op;
-  code = tsdbSttFileWriterClose(&pCommitter->sttWriter, 0, &op);
+  STFileOp op[1];
+  code = tsdbSttFileWriterClose(&committer->sttWriter, 0, op);
   TSDB_CHECK_CODE(code, lino, _exit);
 
-  if (op.optype != TSDB_FOP_NONE) {
-    code = TARRAY2_APPEND(pCommitter->fopArray, op);
+  if (op->optype != TSDB_FOP_NONE) {
+    code = TARRAY2_APPEND_PTR(committer->fopArray, op);
     TSDB_CHECK_CODE(code, lino, _exit);
   }
 
+  tsdbIterMergerClose(&committer->iterMerger);
+  TARRAY2_CLEAR(committer->iterArray, tsdbIterClose);
+
 _exit:
   if (code) {
-    tsdbError("vgId:%d failed at line %d since %s", vid, lino, tstrerror(code));
+    TSDB_ERROR_LOG(TD_VID(committer->tsdb->pVnode), lino, code);
   } else {
-    tsdbDebug("vgId:%d %s done, fid:%d", vid, __func__, pCommitter->ctx->fid);
+    tsdbDebug("vgId:%d %s done, fid:%d", TD_VID(committer->tsdb->pVnode), __func__, committer->ctx->fid);
   }
   return code;
 }
@@ -349,20 +365,24 @@ static int32_t tsdbOpenCommitter(STsdb *tsdb, SCommitInfo *info, SCommitter2 *co
   memset(committer, 0, sizeof(committer[0]));
 
   committer->tsdb = tsdb;
+  code = tsdbFSCreateCopySnapshot(tsdb->pFS, &committer->fsetArr);
+  TSDB_CHECK_CODE(code, lino, _exit);
+
   committer->minutes = tsdb->keepCfg.days;
   committer->precision = tsdb->keepCfg.precision;
   committer->minRow = info->info.config.tsdbCfg.minRows;
   committer->maxRow = info->info.config.tsdbCfg.maxRows;
   committer->cmprAlg = info->info.config.tsdbCfg.compression;
   committer->sttTrigger = info->info.config.sttTrigger;
-  committer->compactVersion = INT64_MAX;  // TODO: use a function
-
-  TARRAY2_INIT(committer->fopArray);
-  tsdbFSAllocEid(tsdb->pFS, &committer->eid);
+  committer->szPage = info->info.config.tsdbPageSize;
+  committer->compactVersion = INT64_MAX;
 
+  committer->ctx->cid = tsdbFSAllocEid(tsdb->pFS);
   committer->ctx->now = taosGetTimestampSec();
   committer->ctx->nextKey = tsdb->imem->minKey;  // TODO
 
+  TARRAY2_INIT(committer->fopArray);
+
 _exit:
   if (code) {
     TSDB_ERROR_LOG(vid, lino, code);
@@ -372,28 +392,32 @@ _exit:
   return code;
 }
 
-static int32_t tsdbCloseCommitter(SCommitter2 *pCommiter, int32_t eno) {
+static int32_t tsdbCloseCommitter(SCommitter2 *committer, int32_t eno) {
   int32_t code = 0;
   int32_t lino = 0;
-  int32_t vid = TD_VID(pCommiter->tsdb->pVnode);
+  int32_t vid = TD_VID(committer->tsdb->pVnode);
 
   if (eno == 0) {
-    code = tsdbFSEditBegin(pCommiter->tsdb->pFS, pCommiter->fopArray, TSDB_FEDIT_COMMIT);
+    code = tsdbFSEditBegin(committer->tsdb->pFS, committer->fopArray, TSDB_FEDIT_COMMIT);
     TSDB_CHECK_CODE(code, lino, _exit);
   } else {
     // TODO
     ASSERT(0);
   }
 
-  ASSERT(pCommiter->sttWriter == NULL);
-  TARRAY2_FREE(pCommiter->fopArray);
+  ASSERT(committer->dataWriter == NULL);
+  ASSERT(committer->sttWriter == NULL);
+  ASSERT(committer->iterMerger == NULL);
+  TARRAY2_FREE(committer->iterArray);
+  TARRAY2_FREE(committer->fopArray);
+  tsdbFSDestroyCopySnapshot(&committer->fsetArr);
 
 _exit:
   if (code) {
     tsdbError("vgId:%d %s failed at line %d since %s, eid:%" PRId64, vid, __func__, lino, tstrerror(code),
-              pCommiter->eid);
+              committer->ctx->cid);
   } else {
-    tsdbDebug("vgId:%d %s done, eid:%" PRId64, vid, __func__, pCommiter->eid);
+    tsdbDebug("vgId:%d %s done, eid:%" PRId64, vid, __func__, committer->ctx->cid);
   }
   return code;
 }
@@ -413,15 +437,15 @@ int32_t tsdbCommitBegin(STsdb *tsdb, SCommitInfo *info) {
   int32_t    code = 0;
   int32_t    lino = 0;
   int32_t    vid = TD_VID(tsdb->pVnode);
-  SMemTable *memt = tsdb->imem;
-  int64_t    nRow = memt->nRow;
-  int64_t    nDel = memt->nDel;
+  SMemTable *imem = tsdb->imem;
+  int64_t    nRow = imem->nRow;
+  int64_t    nDel = imem->nDel;
 
   if (!nRow && !nDel) {
     taosThreadRwlockWrlock(&tsdb->rwLock);
     tsdb->imem = NULL;
     taosThreadRwlockUnlock(&tsdb->rwLock);
-    tsdbUnrefMemTable(memt, NULL, true);
+    tsdbUnrefMemTable(imem, NULL, true);
   } else {
     SCommitter2 committer[1];
 
@@ -430,10 +454,7 @@ int32_t tsdbCommitBegin(STsdb *tsdb, SCommitInfo *info) {
 
     while (committer->ctx->nextKey != TSKEY_MAX) {
       code = tsdbCommitFileSet(committer);
-      if (code) {
-        lino = __LINE__;
-        break;
-      }
+      TSDB_CHECK_CODE(code, lino, _exit);
     }
 
     code = tsdbCloseCommitter(committer, code);
@@ -449,33 +470,32 @@ _exit:
   return code;
 }
 
-int32_t tsdbCommitCommit(STsdb *pTsdb) {
+int32_t tsdbCommitCommit(STsdb *tsdb) {
   int32_t code = 0;
   int32_t lino = 0;
-  int32_t vid = TD_VID(pTsdb->pVnode);
 
-  if (pTsdb->imem == NULL) goto _exit;
+  if (tsdb->imem == NULL) goto _exit;
 
-  SMemTable *pMemTable = pTsdb->imem;
-  taosThreadRwlockWrlock(&pTsdb->rwLock);
-  code = tsdbFSEditCommit(pTsdb->pFS);
+  SMemTable *pMemTable = tsdb->imem;
+  taosThreadRwlockWrlock(&tsdb->rwLock);
+  code = tsdbFSEditCommit(tsdb->pFS);
   if (code) {
-    taosThreadRwlockUnlock(&pTsdb->rwLock);
+    taosThreadRwlockUnlock(&tsdb->rwLock);
     TSDB_CHECK_CODE(code, lino, _exit);
   }
-  pTsdb->imem = NULL;
-  taosThreadRwlockUnlock(&pTsdb->rwLock);
+  tsdb->imem = NULL;
+  taosThreadRwlockUnlock(&tsdb->rwLock);
   tsdbUnrefMemTable(pMemTable, NULL, true);
 
   // TODO: make this call async
-  code = tsdbMerge(pTsdb);
+  code = tsdbMerge(tsdb);
   TSDB_CHECK_CODE(code, lino, _exit);
 
 _exit:
   if (code) {
-    tsdbError("vgId:%d, %s failed at line %d since %s", vid, __func__, lino, tstrerror(code));
+    TSDB_ERROR_LOG(TD_VID(tsdb->pVnode), lino, code);
   } else {
-    tsdbInfo("vgId:%d %s done", vid, __func__);
+    tsdbInfo("vgId:%d %s done", TD_VID(tsdb->pVnode), __func__);
   }
   return code;
 }
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbFS.c b/source/dnode/vnode/src/tsdb/dev/tsdbFS.c
index f9663398dc..aa86a19878 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbFS.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbFS.c
@@ -538,9 +538,11 @@ int32_t tsdbCloseFS(STFileSystem **ppFS) {
   return 0;
 }
 
-int32_t tsdbFSAllocEid(STFileSystem *pFS, int64_t *eid) {
-  eid[0] = ++pFS->neid;  // TODO: use atomic operation
-  return 0;
+int64_t tsdbFSAllocEid(STFileSystem *fs) {
+  taosThreadRwlockRdlock(&fs->tsdb->rwLock);
+  int64_t cid = ++fs->neid;
+  taosThreadRwlockUnlock(&fs->tsdb->rwLock);
+  return cid;
 }
 
 int32_t tsdbFSEditBegin(STFileSystem *fs, const TFileOpArray *opArray, EFEditT etype) {
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbFSet.c b/source/dnode/vnode/src/tsdb/dev/tsdbFSet.c
index 3a1cf659bb..9bd190b83b 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbFSet.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbFSet.c
@@ -267,7 +267,7 @@ int32_t tsdbTFileSetEdit(STsdb *pTsdb, STFileSet *fset, const STFileOp *op) {
     if (code) return code;
 
     if (fobj->f->type == TSDB_FTYPE_STT) {
-      SSttLvl *lvl = tsdbTFileSetGetLvl(fset, fobj->f->stt->level);
+      SSttLvl *lvl = tsdbTFileSetGetSttLvl(fset, fobj->f->stt->level);
       if (!lvl) {
         code = tsdbSttLvlInit(fobj->f->stt->level, &lvl);
         if (code) return code;
@@ -285,7 +285,7 @@ int32_t tsdbTFileSetEdit(STsdb *pTsdb, STFileSet *fset, const STFileOp *op) {
   } else if (op->optype == TSDB_FOP_REMOVE) {
     // delete a file
     if (op->of.type == TSDB_FTYPE_STT) {
-      SSttLvl *lvl = tsdbTFileSetGetLvl(fset, op->of.stt->level);
+      SSttLvl *lvl = tsdbTFileSetGetSttLvl(fset, op->of.stt->level);
       ASSERT(lvl);
 
       STFileObj  tfobj = {.f[0] = {.cid = op->of.cid}};
@@ -305,7 +305,7 @@ int32_t tsdbTFileSetEdit(STsdb *pTsdb, STFileSet *fset, const STFileOp *op) {
     }
   } else {
     if (op->nf.type == TSDB_FTYPE_STT) {
-      SSttLvl *lvl = tsdbTFileSetGetLvl(fset, op->of.stt->level);
+      SSttLvl *lvl = tsdbTFileSetGetSttLvl(fset, op->of.stt->level);
       ASSERT(lvl);
 
       STFileObj tfobj = {.f[0] = {.cid = op->of.cid}}, *tfobjp = &tfobj;
@@ -463,9 +463,9 @@ int32_t tsdbTFileSetRemove(STFileSet **fset) {
   return 0;
 }
 
-SSttLvl *tsdbTFileSetGetLvl(STFileSet *fset, int32_t level) {
-  SSttLvl  tlvl = {.level = level};
-  SSttLvl *lvl = &tlvl;
+SSttLvl *tsdbTFileSetGetSttLvl(STFileSet *fset, int32_t level) {
+  SSttLvl  sttLvl = {.level = level};
+  SSttLvl *lvl = &sttLvl;
   return TARRAY2_SEARCH_EX(fset->lvlArr, &lvl, tsdbSttLvlCmprFn, TD_EQ);
 }
 
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbIter.c b/source/dnode/vnode/src/tsdb/dev/tsdbIter.c
index 0ce006df72..2c578fe7af 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbIter.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbIter.c
@@ -348,7 +348,7 @@ struct SIterMerger {
   SRBTree    iterTree[1];
 };
 
-int32_t tsdbIterMergerInit(const TTsdbIterArray *iterArray, SIterMerger **merger) {
+int32_t tsdbIterMergerOpen(const TTsdbIterArray *iterArray, SIterMerger **merger) {
   STsdbIter   *iter;
   SRBTreeNode *node;
 
@@ -365,7 +365,7 @@ int32_t tsdbIterMergerInit(const TTsdbIterArray *iterArray, SIterMerger **merger
   return tsdbIterMergerNext(merger[0]);
 }
 
-int32_t tsdbIterMergerClear(SIterMerger **merger) {
+int32_t tsdbIterMergerClose(SIterMerger **merger) {
   if (merger[0]) {
     taosMemoryFree(merger[0]);
     merger[0] = NULL;
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbMerge.c b/source/dnode/vnode/src/tsdb/dev/tsdbMerge.c
index 3310502359..73dd5465fc 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbMerge.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbMerge.c
@@ -57,7 +57,7 @@ static int32_t tsdbMergerOpen(SMerger *merger) {
   merger->szPage = merger->tsdb->pVnode->config.tsdbPageSize;
   merger->cmprAlg = merger->tsdb->pVnode->config.tsdbCfg.compression;
   merger->compactVersion = INT64_MAX;
-  tsdbFSAllocEid(merger->tsdb->pFS, &merger->cid);
+  merger->cid = tsdbFSAllocEid(merger->tsdb->pFS);
   merger->ctx->opened = true;
   return 0;
 }
@@ -273,7 +273,7 @@ static int32_t tsdbMergeFileSetBeginOpenIter(SMerger *merger) {
     }
   }
 
-  code = tsdbIterMergerInit(merger->iterArr, &merger->iterMerger);
+  code = tsdbIterMergerOpen(merger->iterArr, &merger->iterMerger);
   TSDB_CHECK_CODE(code, lino, _exit);
 
 _exit:
@@ -444,7 +444,7 @@ _exit:
 }
 
 static int32_t tsdbMergeFileSetEndCloseIter(SMerger *merger) {
-  tsdbIterMergerClear(&merger->iterMerger);
+  tsdbIterMergerClose(&merger->iterMerger);
   TARRAY2_CLEAR(merger->iterArr, tsdbIterClose);
   return 0;
 }
@@ -566,5 +566,5 @@ _exit:
   } else if (merger->ctx->opened) {
     tsdbDebug("vgId:%d %s done", vid, __func__);
   }
-  return 0;
+  return code;
 }
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbSttFileRW.c b/source/dnode/vnode/src/tsdb/dev/tsdbSttFileRW.c
index 8b770ed5e9..5251e79df1 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbSttFileRW.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbSttFileRW.c
@@ -28,6 +28,7 @@ struct SSttFileReader {
   SSttFileReaderConfig config[1];
   TSttSegReaderArray   readerArray[1];
   STsdbFD             *fd;
+  uint8_t             *bufArr[5];
 };
 
 struct SSttSegReader {
@@ -87,6 +88,7 @@ int32_t tsdbSttFileReaderOpen(const char *fname, const SSttFileReaderConfig *con
   if (reader[0] == NULL) return TSDB_CODE_OUT_OF_MEMORY;
 
   reader[0]->config[0] = config[0];
+  if (!reader[0]->config->bufArr) reader[0]->config->bufArr = reader[0]->bufArr;
 
   // open file
   code = tsdbOpenFile(fname, config->szPage, TD_FILE_READ, &reader[0]->fd);
@@ -118,6 +120,9 @@ _exit:
 
 int32_t tsdbSttFileReaderClose(SSttFileReader **reader) {
   if (reader[0]) {
+    for (int32_t i = 0; i < ARRAY_SIZE(reader[0]->bufArr); ++i) {
+      tFree(reader[0]->bufArr[i]);
+    }
     tsdbCloseFile(&reader[0]->fd);
     TARRAY2_CLEAR_FREE(reader[0]->readerArray, tsdbSttSegReaderClose);
     taosMemoryFree(reader[0]);