partial work

src/inc/tfs.h

@@ -57,6 +57,7 @@ typedef struct {
 #define TFILE_NAME(pf) ((pf)->aname)
 
 void tfsInitFile(TFILE *pf, int level, int id, const char *bname);
+bool tfsIsSameFile(TFILE *pf1, TFILE *pf2);
 void tfsSetLevel(TFILE *pf, int level);
 void tfsSetID(TFILE *pf, int id);
 int  tfsopen(TFILE *pf, int flags);

src/tfs/src/tfs.c

@@ -175,6 +175,13 @@ void tfsInitFile(TFILE *pf, int level, int id, const char *bname) {
   tfsSetFileAname(pf);
 }
 
+bool tfsIsSameFile(TFILE *pf1, TFILE *pf2) {
+  if (pf1->level != pf2->level) return false;
+  if (pf1->id != pf2->id) return false;
+  if (strncmp(pf1->rname, pf2->rname, TSDB_FILENAME_LEN) != 0) return false;
+  return true;
+}
+
 void tfsSetLevel(TFILE *pf, int level) {
   pf->level = level;
 

src/tsdb/CMakeLists.txt

@@ -3,6 +3,7 @@ PROJECT(TDengine)
 
 INCLUDE_DIRECTORIES(inc)
 AUX_SOURCE_DIRECTORY(src SRC)
+list(REMOVE_ITEM SRC "src/tsdbFS.c")
 ADD_LIBRARY(tsdb ${SRC})
 TARGET_LINK_LIBRARIES(tsdb tfs common tutil)
 

src/tsdb/inc/tsdbMain.h

@@ -45,10 +45,6 @@ extern int32_t tsdbDebugFlag;
 #define tsdbTrace(...) do { if (tsdbDebugFlag & DEBUG_TRACE) { taosPrintLog("TDB ", tsdbDebugFlag, __VA_ARGS__); }} while(0)
 
 // ================= OTHERS
-#define TSDB_MAX_TABLE_SCHEMAS 16
-#define TSDB_FILE_HEAD_SIZE    512
-#define TSDB_FILE_DELIMITER    0xF00AFA0F
-#define TSDB_FILE_INIT_MAGIC   0xFFFFFFFF
 
 #define TAOS_IN_RANGE(key, keyMin, keyLast) (((key) >= (keyMin)) && ((key) <= (keyMax)))
 
@@ -58,6 +54,8 @@ extern int32_t tsdbDebugFlag;
 
 // Definitions
 // ================= tsdbMeta.c
+#define TSDB_MAX_TABLE_SCHEMAS 16
+
 typedef struct STable {
   STableId       tableId;
   ETableType     type;
@@ -295,102 +293,211 @@ static FORCE_INLINE TKEY tsdbNextIterTKey(SSkipListIterator* pIter) {
   return dataRowTKey(row);
 }
 
-// ================= tsdbFile.c
-extern const char* tsdbFileSuffix[];
+// ================= tsdbFS.c
+#define TSDB_FILE_HEAD_SIZE 512
+#define TSDB_FILE_DELIMITER 0xF00AFA0F
+#define TSDB_FILE_INIT_MAGIC 0xFFFFFFFF
 
-// minFid <= midFid <= maxFid
+enum { TSDB_FILE_HEAD = 0, TSDB_FILE_DATA, TSDB_FILE_LAST, TSDB_FILE_MAX };
+
+// For meta file
 typedef struct {
-  int minFid;  // >= minFid && < midFid, at level 2
-  int midFid;  // >= midFid && < maxFid, at level 1
-  int maxFid;  // >= maxFid, at level 0
-} SFidGroup;
-
-typedef enum {
-  TSDB_FILE_TYPE_HEAD = 0,
-  TSDB_FILE_TYPE_DATA,
-  TSDB_FILE_TYPE_LAST,
-  TSDB_FILE_TYPE_STAT,
-  TSDB_FILE_TYPE_NHEAD,
-  TSDB_FILE_TYPE_NDATA,
-  TSDB_FILE_TYPE_NLAST,
-  TSDB_FILE_TYPE_NSTAT
-} TSDB_FILE_TYPE;
-
-#ifndef TDINTERNAL
-#define TSDB_FILE_TYPE_MAX (TSDB_FILE_TYPE_LAST+1)
-#else
-#define TSDB_FILE_TYPE_MAX (TSDB_FILE_TYPE_STAT+1)
-#endif
+  int64_t  size;
+  int64_t  tombSize;
+  int64_t  nRecords;
+  int64_t  nDels;
+  uint32_t magic;
+} SMFInfo;
+
+typedef struct {
+  SMFInfo info;
+  TFILE   f;
+  int     fd;
+} SMFile;
 
+// For .head/.data/.last file
 typedef struct {
   uint32_t magic;
   uint32_t len;
   uint32_t totalBlocks;
   uint32_t totalSubBlocks;
   uint32_t offset;
-  uint64_t size;      // total size of the file
-  uint64_t tombSize;  // unused file size
-} STsdbFileInfo;
+  uint64_t size;
+  uint64_t tombSize;
+} SDFInfo;
 
 typedef struct {
-  TFILE         file;
-  STsdbFileInfo info;
-  int           fd;
-} SFile;
+  SDFInfo info;
+  TFILE   f;
+  int     fd;
+} SDFile;
 
 typedef struct {
-  int   fileId;
-  int   state; // 0 for health, 1 for problem
-  SFile files[TSDB_FILE_TYPE_MAX];
-} SFileGroup;
+  int    id;
+  int    state;
+  SDFile files[TSDB_FILE_MAX];
+} SDFileSet;
 
+/* Statistic information of the TSDB file system.
+ */
 typedef struct {
-  pthread_rwlock_t fhlock;
+  int64_t fsversion; // file system version, related to program
+  int64_t version;
+  int64_t totalPoints;
+  int64_t totalStorage;
+} STsdbFSMeta;
 
-  int         maxFGroups;
-  int         nFGroups;
-  SFileGroup* pFGroup;
-} STsdbFileH;
+typedef struct {
+  int64_t     version;
+  STsdbFSMeta meta;
+  SMFile      mf;  // meta file
+  SArray *    df;  // data file array
+} SFSSnapshot;
 
 typedef struct {
-  int         direction;
-  STsdbFileH* pFileH;
-  int         fileId;
-  int         index;
-} SFileGroupIter;
-
-#define TSDB_FILE_NAME(pFile) ((pFile)->file.aname)
-#define TSDB_KEY_FILEID(key, daysPerFile, precision) ((key) / tsMsPerDay[(precision)] / (daysPerFile))
-#define TSDB_MAX_FILE(keep, daysPerFile) ((keep) / (daysPerFile) + 3)
-#define TSDB_MIN_FILE_ID(fh) (fh)->pFGroup[0].fileId
-#define TSDB_MAX_FILE_ID(fh) (fh)->pFGroup[(fh)->nFGroups - 1].fileId
-#define TSDB_IS_FILE_OPENED(f) ((f)->fd > 0)
-#define TSDB_FGROUP_ITER_FORWARD TSDB_ORDER_ASC
-#define TSDB_FGROUP_ITER_BACKWARD TSDB_ORDER_DESC
-
-STsdbFileH* tsdbNewFileH(STsdbCfg* pCfg);
-void        tsdbFreeFileH(STsdbFileH* pFileH);
-int         tsdbOpenFileH(STsdbRepo* pRepo);
-void        tsdbCloseFileH(STsdbRepo* pRepo, bool isRestart);
-SFileGroup *tsdbCreateFGroup(STsdbRepo *pRepo, int fid, int level);
-void        tsdbInitFileGroupIter(STsdbFileH* pFileH, SFileGroupIter* pIter, int direction);
-void        tsdbSeekFileGroupIter(SFileGroupIter* pIter, int fid);
-SFileGroup* tsdbGetFileGroupNext(SFileGroupIter* pIter);
-int         tsdbOpenFile(SFile* pFile, int oflag);
-void        tsdbCloseFile(SFile* pFile);
-int         tsdbCreateFile(SFile* pFile, STsdbRepo* pRepo, int fid, int type);
-SFileGroup* tsdbSearchFGroup(STsdbFileH* pFileH, int fid, int flags);
-int         tsdbGetFidLevel(int fid, SFidGroup fidg);
-void        tsdbRemoveFilesBeyondRetention(STsdbRepo* pRepo, SFidGroup* pFidGroup);
-int         tsdbUpdateFileHeader(SFile* pFile);
-int         tsdbEncodeSFileInfo(void** buf, const STsdbFileInfo* pInfo);
-void*       tsdbDecodeSFileInfo(void* buf, STsdbFileInfo* pInfo);
-void        tsdbRemoveFileGroup(STsdbRepo* pRepo, SFileGroup* pFGroup);
-int         tsdbLoadFileHeader(SFile* pFile, uint32_t* version);
-void        tsdbGetFileInfoImpl(char* fname, uint32_t* magic, int64_t* size);
-void        tsdbGetFidGroup(STsdbCfg* pCfg, SFidGroup* pFidGroup);
-void        tsdbGetFidKeyRange(int daysPerFile, int8_t precision, int fileId, TSKEY *minKey, TSKEY *maxKey);
-int         tsdbApplyRetention(STsdbRepo* pRepo, SFidGroup *pFidGroup);
+  pthread_rwlock_t lock;
+
+  SFSSnapshot *curr;
+  SFSSnapshot *new;
+} STsdbFS;
+
+#define TSDB_FILE_INFO(tf) (&((tf)->info))
+#define TSDB_FILE_F(tf) (&((tf)->f)))
+#define TSDB_FILE_FD(tf) ((tf)->fd)
+
+int  tsdbOpenFS(STsdbRepo *pRepo);
+void tsdbCloseFS(STsdbRepo *pRepo);
+int  tsdbFSNewTxn(STsdbRepo *pRepo);
+int  tsdbFSEndTxn(STsdbRepo *pRepo, bool hasError);
+int  tsdbUpdateMFile(STsdbRepo *pRepo, SMFile *pMFile);
+int  tsdbUpdateDFileSet(STsdbRepo *pRepo, SDFileSet *pSet);
+void tsdbRemoveExpiredDFileSet(STsdbRepo *pRepo, int mfid);
+int  tsdbRemoveDFileSet(SDFileSet *pSet);
+
+static FORCE_INLINE int tsdbRLockFS(STsdbFS *pFs) {
+  int code = pthread_rwlock_rdlock(&(pFs->lock));
+  if (code != 0) {
+    terrno = TAOS_SYSTEM_ERROR(code);
+    return -1;
+  }
+  return 0;
+}
+
+static FORCE_INLINE int tsdbWLockFS(STsdbFS *pFs) {
+  int code = pthread_rwlock_wrlock(&(pFs->lock));
+  if (code != 0) {
+    terrno = TAOS_SYSTEM_ERROR(code);
+    return -1;
+  }
+  return 0;
+}
+
+static FORCE_INLINE int tsdbUnLockFS(STsdbFS *pFs) {
+  int code = pthread_rwlock_unlock(&(pFs->lock));
+  if (code != 0) {
+    terrno = TAOS_SYSTEM_ERROR(code);
+    return -1;
+  }
+  return 0;
+}
+
+
+// ================= tsdbFile.c
+// extern const char* tsdbFileSuffix[];
+
+// minFid <= midFid <= maxFid
+// typedef struct {
+//   int minFid;  // >= minFid && < midFid, at level 2
+//   int midFid;  // >= midFid && < maxFid, at level 1
+//   int maxFid;  // >= maxFid, at level 0
+// } SFidGroup;
+
+// typedef enum {
+//   TSDB_FILE_TYPE_HEAD = 0,
+//   TSDB_FILE_TYPE_DATA,
+//   TSDB_FILE_TYPE_LAST,
+//   TSDB_FILE_TYPE_STAT,
+//   TSDB_FILE_TYPE_NHEAD,
+//   TSDB_FILE_TYPE_NDATA,
+//   TSDB_FILE_TYPE_NLAST,
+//   TSDB_FILE_TYPE_NSTAT
+// } TSDB_FILE_TYPE;
+
+// #ifndef TDINTERNAL
+// #define TSDB_FILE_TYPE_MAX (TSDB_FILE_TYPE_LAST+1)
+// #else
+// #define TSDB_FILE_TYPE_MAX (TSDB_FILE_TYPE_STAT+1)
+// #endif
+
+// typedef struct {
+//   uint32_t magic;
+//   uint32_t len;
+//   uint32_t totalBlocks;
+//   uint32_t totalSubBlocks;
+//   uint32_t offset;
+//   uint64_t size;      // total size of the file
+//   uint64_t tombSize;  // unused file size
+// } STsdbFileInfo;
+
+// typedef struct {
+//   TFILE         file;
+//   STsdbFileInfo info;
+//   int           fd;
+// } SFile;
+
+// typedef struct {
+//   int   fileId;
+//   int   state; // 0 for health, 1 for problem
+//   SFile files[TSDB_FILE_TYPE_MAX];
+// } SFileGroup;
+
+// typedef struct {
+//   pthread_rwlock_t fhlock;
+
+//   int         maxFGroups;
+//   int         nFGroups;
+//   SFileGroup* pFGroup;
+// } STsdbFileH;
+
+// typedef struct {
+//   int         direction;
+//   STsdbFileH* pFileH;
+//   int         fileId;
+//   int         index;
+// } SFileGroupIter;
+
+// #define TSDB_FILE_NAME(pFile) ((pFile)->file.aname)
+// #define TSDB_KEY_FILEID(key, daysPerFile, precision) ((key) / tsMsPerDay[(precision)] / (daysPerFile))
+// #define TSDB_MAX_FILE(keep, daysPerFile) ((keep) / (daysPerFile) + 3)
+// #define TSDB_MIN_FILE_ID(fh) (fh)->pFGroup[0].fileId
+// #define TSDB_MAX_FILE_ID(fh) (fh)->pFGroup[(fh)->nFGroups - 1].fileId
+// #define TSDB_IS_FILE_OPENED(f) ((f)->fd > 0)
+// #define TSDB_FGROUP_ITER_FORWARD TSDB_ORDER_ASC
+// #define TSDB_FGROUP_ITER_BACKWARD TSDB_ORDER_DESC
+
+// STsdbFileH* tsdbNewFileH(STsdbCfg* pCfg);
+// void        tsdbFreeFileH(STsdbFileH* pFileH);
+// int         tsdbOpenFileH(STsdbRepo* pRepo);
+// void        tsdbCloseFileH(STsdbRepo* pRepo, bool isRestart);
+// SFileGroup *tsdbCreateFGroup(STsdbRepo *pRepo, int fid, int level);
+// void        tsdbInitFileGroupIter(STsdbFileH* pFileH, SFileGroupIter* pIter, int direction);
+// void        tsdbSeekFileGroupIter(SFileGroupIter* pIter, int fid);
+// SFileGroup* tsdbGetFileGroupNext(SFileGroupIter* pIter);
+// int         tsdbOpenFile(SFile* pFile, int oflag);
+// void        tsdbCloseFile(SFile* pFile);
+// int         tsdbCreateFile(SFile* pFile, STsdbRepo* pRepo, int fid, int type);
+// SFileGroup* tsdbSearchFGroup(STsdbFileH* pFileH, int fid, int flags);
+// int         tsdbGetFidLevel(int fid, SFidGroup fidg);
+// void        tsdbRemoveFilesBeyondRetention(STsdbRepo* pRepo, SFidGroup* pFidGroup);
+// int         tsdbUpdateFileHeader(SFile* pFile);
+// int         tsdbEncodeSFileInfo(void** buf, const STsdbFileInfo* pInfo);
+// void*       tsdbDecodeSFileInfo(void* buf, STsdbFileInfo* pInfo);
+// void        tsdbRemoveFileGroup(STsdbRepo* pRepo, SFileGroup* pFGroup);
+// int         tsdbLoadFileHeader(SFile* pFile, uint32_t* version);
+// void        tsdbGetFileInfoImpl(char* fname, uint32_t* magic, int64_t* size);
+// void        tsdbGetFidGroup(STsdbCfg* pCfg, SFidGroup* pFidGroup);
+// void        tsdbGetFidKeyRange(int daysPerFile, int8_t precision, int fileId, TSKEY *minKey, TSKEY *maxKey);
+// int         tsdbApplyRetention(STsdbRepo* pRepo, SFidGroup *pFidGroup);
 
 // ================= tsdbMain.c
 typedef struct {
@@ -416,7 +523,7 @@ struct STsdbRepo {
   STsdbBufPool*   pPool;
   SMemTable*      mem;
   SMemTable*      imem;
-  STsdbFileH*     tsdbFileH;
+  STsdbFS*        fs;
   sem_t           readyToCommit;
   pthread_mutex_t mutex;
   bool            repoLocked;

src/tsdb/src/tsdbCommit.c

@@ -147,8 +147,8 @@ static int tsdbCommitMeta(STsdbRepo *pRepo) {
     goto _err;
   }
 
-  // TODO
-  // tsdbUpdateMFile(pRepo, NULL)
+  // TODO: update meta file
+  tsdbUpdateMFile(pRepo, NULL);
 
   return 0;
 
@@ -162,13 +162,17 @@ static int tsdbStartCommit(STsdbRepo *pRepo) {
   tsdbInfo("vgId:%d start to commit! keyFirst %" PRId64 " keyLast %" PRId64 " numOfRows %" PRId64 " meta rows: %d",
            REPO_ID(pRepo), pMem->keyFirst, pMem->keyLast, pMem->numOfRows, listNEles(pMem->actList));
 
-  // TODO
+  if (tsdbFSNewTxn(pRepo) < 0) return -1;
 
   pRepo->code = TSDB_CODE_SUCCESS;
   return 0;
 }
 
 static void tsdbEndCommit(STsdbRepo *pRepo, int eno) {
+  if (tsdbFSEndTxn(pRepo, eno != TSDB_CODE_SUCCESS) < 0) {
+    eno = terrno;
+  }
+
   tsdbInfo("vgId:%d commit over, %s", REPO_ID(pRepo), (eno == TSDB_CODE_SUCCESS) ? "succeed" : "failed");
 
   if (pRepo->appH.notifyStatus) pRepo->appH.notifyStatus(pRepo->appH.appH, TSDB_STATUS_COMMIT_OVER, eno);

src/tsdb/src/tsdbFS.c

+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+
+#include "tsdbMain.h"
+
+#define REPO_FS(r) ((r)->fs)
+#define TSDB_MAX_DFILES(keep, days) ((keep) / (days) + 3)
+
+int tsdbOpenFS(STsdbRepo *pRepo) {
+  ASSERT(REPO_FS == NULL);
+
+  STsdbCfg *pCfg = TSDB_CFG(pRepo);
+
+  // Create fs object
+  REPO_FS(pRepo) = tsdbNewFS(pCfg->keep, pCfg->daysPerFile);
+  if (REPO_FS(pRepo) == NULL) {
+    tsdbError("vgId:%d failed to open TSDB FS since %s", REPO_ID(pRepo), tstrerror(terrno));
+    return -1;
+  }
+
+  // Load TSDB file system from disk
+  if (tsdbOpenFSImpl(pRepo) < 0) {
+    tsdbError("vgId:%d failed to open TSDB FS since %s", REPO_ID(pRepo), tstrerror(terrno));
+    tsdbCloseFS(pRepo);
+    return -1;
+  }
+
+  return 0;
+}
+
+void tsdbCloseFS(STsdbRepo *pRepo) {
+  REPO_FS(pRepo) = tsdbFreeFS(REPO_FS(pRepo));
+  return 0;
+}
+
+// Start a new FS transaction
+int tsdbFSNewTxn(STsdbRepo *pRepo) {
+  STsdbFS *pFs = REPO_FS(pRepo);
+
+  if (tsdbCopySnapshot(pFs->curr, pFs->new) < 0) {
+    return -1;
+  }
+
+  pFs->new->version++;
+
+  return 0;
+}
+
+// End an existing FS transaction
+int tsdbFSEndTxn(STsdbRepo *pRepo, bool hasError) {
+  STsdbFS *pFs = REPO_FS(pRepo);
+
+  if (hasError) { // roll back files
+
+  } else { // apply file change
+    if (tsdbSaveFSSnapshot(-1, pFs->new) < 0) {
+      // TODO
+    }
+
+    // rename();
+
+    // apply all file changes
+
+  }
+
+  return 0;
+}
+
+int tsdbUpdateMFile(STsdbRepo *pRepo, SMFile *pMFile) {
+  STsdbFS *pFs = REPO_FS(pRepo);
+  pFs->new->mf = *pMFile;
+  return 0;
+}
+
+int tsdbUpdateDFileSet(STsdbRepo *pRepo, SDFileSet *pSet) {
+  SFSSnapshot *pSnapshot = REPO_FS(pRepo)->new;
+  SDFileSet *  pOldSet;
+
+  pOldSet = tsdbSearchDFileSet(pSnapshot, pSet->id, TD_GE);
+  if (pOldSet == NULL) {
+    if (taosArrayPush(pSnapshot->df, pSet) == NULL) {
+      terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
+      return -1;
+    }
+  } else {
+    int index = TARRAY_ELEM_IDX(dfArray, ptr);
+
+    if (pOldSet->id == pSet->id) {
+      taosArraySet(pSnapshot->df, index, pSet);
+    } else if (pOldSet->id > pSet->id) {
+      if (taosArrayInsert(pSnapshot->df, index, pSet) == NULL) {
+        terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
+        return -1;
+      }
+    } else {
+      ASSERT(0);
+    }
+  }
+
+  return 0;
+}
+
+void tsdbRemoveExpiredDFileSet(STsdbRepo *pRepo, int mfid) {
+  SFSSnapshot *pSnapshot = REPO_FS(pRepo)->new;
+  while (taosArrayGetSize(pSnapshot->df) > 0) {
+    SDFileSet *pSet = (SDFileSet *)taosArrayGet(pSnapshot->df, 0);
+    if (pSet->id < mfid) {
+      taosArrayRemove(pSnapshot->df, 0);
+    }
+  }
+}
+
+static int tsdbSaveFSSnapshot(int fd, SFSSnapshot *pSnapshot) {
+  // TODO
+  return 0;
+}
+
+static int tsdbLoadFSSnapshot(SFSSnapshot *pSnapshot) {
+  // TODO
+  return 0;
+}
+
+static int tsdbOpenFSImpl(STsdbRepo *pRepo) {
+  char manifest[TSDB_FILENAME_LEN] = "\0";
+
+  // TODO: use API here
+  sprintf(manifest, "%s/manifest", pRepo->rootDir);
+
+  if (access(manifest, F_OK) == 0) {
+    // manifest file exist, just load
+    // TODO
+  } else {
+    // manifest file not exists, scan all the files and construct 
+    // TODO
+  }
+
+  return 0;
+}
+
+static int tsdbEncodeMFInfo(void **buf, SMFInfo *pInfo) {
+  int tlen = 0;
+
+  tlen += taosEncodeVariantI64(buf, pInfo->size);
+  tlen += taosEncodeVariantI64(buf, pInfo->tombSize);
+  tlen += taosEncodeVariantI64(buf, pInfo->nRecords);
+  tlen += taosEncodeVariantI64(buf, pInfo->nDels);
+  tlen += taosEncodeFixedU32(buf, pInfo->magic);
+
+  return tlen;
+}
+
+static void *tsdbDecodeMFInfo(void *buf, SMFInfo *pInfo) {
+  buf = taosDecodeVariantI64(buf, &(pInfo->size));
+  buf = taosDecodeVariantI64(buf, &(pInfo->tombSize));
+  buf = taosDecodeVariantI64(buf, &(pInfo->nRecords));
+  buf = taosDecodeVariantI64(buf, &(pInfo->nDels));
+  buf = taosDecodeFixedU32(buf, &(pInfo->magic));
+
+  return buf;
+}
+
+static int tsdbEncodeMFile(void **buf, SMFile *pMFile) {
+  int tlen = 0;
+
+  tlen += tsdbEncodeMFInfo(buf, &(pMFile->info));
+  tlen += tfsEncodeFile(buf, &(pMFile->f));
+
+  return tlen;
+}
+
+static void *tsdbDecodeMFile(void *buf, SMFile *pMFile) {
+  buf = tsdbDecodeMFInfo(buf, &(pMFile->info));
+  buf = tfsDecodeFile(buf, &(pMFile->f));
+
+  return buf;
+}
+
+static int tsdbEncodeDFInfo(void **buf, SDFInfo *pInfo) {
+  int tlen = 0;
+
+  tlen += taosEncodeFixedU32(buf, pInfo->magic);
+  tlen += taosEncodeFixedU32(buf, pInfo->len);
+  tlen += taosEncodeFixedU32(buf, pInfo->totalBlocks);
+  tlen += taosEncodeFixedU32(buf, pInfo->totalSubBlocks);
+  tlen += taosEncodeFixedU32(buf, pInfo->offset);
+  tlen += taosEncodeFixedU64(buf, pInfo->size);
+  tlen += taosEncodeFixedU64(buf, pInfo->tombSize);
+
+  return tlen;
+}
+
+static void *tsdbDecodeDFInfo(void *buf, SDFInfo *pInfo) {
+  buf = taosDecodeFixedU32(buf, &(pInfo->magic));
+  buf = taosDecodeFixedU32(buf, &(pInfo->len));
+  buf = taosDecodeFixedU32(buf, &(pInfo->totalBlocks));
+  buf = taosDecodeFixedU32(buf, &(pInfo->totalSubBlocks));
+  buf = taosDecodeFixedU32(buf, &(pInfo->offset));
+  buf = taosDecodeFixedU64(buf, &(pInfo->size));
+  buf = taosDecodeFixedU64(buf, &(pInfo->tombSize));
+
+  return buf;
+}
+
+static int tsdbEncodeDFile(void **buf, SDFile *pDFile) {
+  int tlen = 0;
+
+  tlen += tsdbEncodeDFInfo(buf, &(pDFile->info));
+  tlen += tfsEncodeFile(buf, &(pDFile->f));
+
+  return tlen;
+}
+
+static void *tsdbDecodeDFile(void *buf, SDFile *pDFile) {
+  buf = tsdbDecodeDFInfo(buf, &(pDFile->info));
+  buf = tfsDecodeFile(buf, &(pDFile->f));
+
+  return buf;
+}
+
+static int tsdbEncodeFSMeta(void **buf, STsdbFSMeta *pMeta) {
+  int tlen = 0;
+
+  tlen += taosEncodeVariantI64(buf, pMeta->fsversion);
+  tlen += taosEncodeVariantI64(buf, pMeta->version);
+  tlen += taosEncodeVariantI64(buf, pMeta->totalPoints);
+  tlen += taosEncodeVariantI64(buf, pMeta->totalStorage);
+
+  return tlen;
+}
+
+static void *tsdbDecodeFSMeta(void *buf, STsdbFSMeta *pMeta) {
+  buf = taosDecodeVariantI64(buf, &(pMeta->fsversion));
+  buf = taosDecodeVariantI64(buf, &(pMeta->version));
+  buf = taosDecodeVariantI64(buf, &(pMeta->totalPoints));
+  buf = taosDecodeVariantI64(buf, &(pMeta->totalStorage));
+
+  return buf;
+}
+
+static int tsdbEncodeFSSnapshot(void **buf, SFSSnapshot *pSnapshot) {
+  int     tlen = 0;
+  int64_t size = 0;
+
+  // Encode meta file
+  tlen += tsdbEncodeMFile(buf, &(pSnapshot->mf));
+
+  // Encode data files
+  size = taosArrayGetSize(pSnapshot->df);
+  tlen += taosEncodeVariantI64(buf, size);
+  for (size_t index = 0; index < size; index++) {
+    SDFile *pFile = taosArrayGet(pSnapshot->df, index);
+    
+    tlen += tsdbEncodeDFInfo(buf, &pFile);
+  }
+  
+
+  return tlen;
+}
+
+static void *tsdbDecodeFSSnapshot(void *buf, SFSSnapshot *pSnapshot) {
+  int64_t size = 0;
+  SDFile  df;
+
+  // Decode meta file
+  buf = tsdbDecodeMFile(buf, &(pSnapshot->mf));
+
+  // Decode data files
+  buf = taosDecodeVariantI64(buf, &size);
+  for (size_t index = 0; index < size; index++) {
+    buf = tsdbDecodeDFInfo(buf, &df);
+    taosArrayPush(pSnapshot->df, (void *)(&df));
+  }
+
+  return buf;
+}
+
+static SFSSnapshot *tsdbNewSnapshot(int32_t nfiles) {
+  SFSSnapshot *pSnapshot;
+
+  pSnapshot = (SFSSnapshot *)calloc(1, sizeof(pSnapshot));
+  if (pSnapshot == NULL) {
+    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
+    return NULL;
+  }
+
+  pSnapshot->df = taosArrayInit(nfiles, sizeof(SDFileSet));
+  if (pSnapshot->df == NULL) {
+    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
+    free(pSnapshot);
+    return NULL;
+  }
+
+  return pSnapshot;
+}
+
+static SFSSnapshot *tsdbFreeSnapshot(SFSSnapshot *pSnapshot) {
+  if (pSnapshot) {
+    taosArrayDestroy(pSnapshot->df);
+    free(pSnapshot);
+  }
+
+  return NULL;
+}
+
+static STsdbFS *tsdbNewFS(int32_t keep, int32_t days) {
+  STsdbFS *pFs;
+  int      code;
+  int32_t  nfiles;
+
+  pFs = (STsdbFS *)calloc(1, sizeof(*pFs));
+  if (pFs == NULL) {
+    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
+    return NULL;
+  }
+
+  code = pthread_rwlock_init(&(pFs->lock));
+  if (code != 0) {
+    terrno = TAOS_SYSTEM_ERROR(code);
+    free(pFs);
+    return NULL;
+  }
+
+  nfiles = TSDB_MAX_DFILES(keep, days);
+  if (((pFs->curr = tsdbNewSnapshot(nfiles)) == NULL) || ((pFs->new = tsdbNewSnapshot(nfiles)) == NULL)) {
+    tsdbFreeFS(pFs);
+    return NULL;
+  }
+
+  return pFs;
+}
+
+static STsdbFS *tsdbFreeFS(STsdbFS *pFs) {
+  if (pFs) {
+    pFs->new = tsdbFreeSnapshot(pFs->new);
+    pFs->curr = tsdbFreeSnapshot(pFs->curr);
+    pthread_rwlock_destroy(&(pFs->lock));
+    free(pFs);
+  }
+
+  return NULL;
+}
+
+static int tsdbCopySnapshot(SFSSnapshot *src, SFSSnapshot *dst) {
+  dst->meta = src->meta;
+  dst->mf = src->meta;
+  taosArrayCopy(dst->df, src->df);
+  return 0;
+}
+
+static int tsdbCompFSetId(const void *key1, const void *key2) {
+  int        id = *(int *)key1;
+  SDFileSet *pSet = (SDFileSet *)key2;
+
+  if (id < pSet->id) {
+    return -1;
+  } else if (id == pSet->id) {
+    return 0;
+  } else {
+    return 1;
+  }
+}
+
+static SDFileSet *tsdbSearchDFileSet(SFSSnapshot *pSnapshot, int fid, int flags) {
+  void *ptr = taosArraySearch(pSnapshot->df, (void *)(&fid), tsdbCompFSetId, flags);
+  return (ptr == NULL) ? NULL : ((SDFileSet *)ptr);
+}
+
+static int tsdbMakeFSChange(STsdbRepo *pRepo) {
+  tsdbMakeFSMFileChange(pRepo);
+  tsdbMakeFSDFileChange(pRepo);
+  return 0;
+}
+
+static int tsdbMakeFSMFileChange(STsdbRepo *pRepo) {
+  STsdbFS *pFs = REPO_FS(pRepo);
+  SMFile * pDstMFile = &(pFs->curr->mf);
+  SMFile * pSrcMFile = &(pFs->new->mf);
+
+  if (tfsIsSameFile(&(pDstMFile->f), &(pSrcMFile->f))) { // the same file
+    if (pDstMFile->info != pSrcMFile->info) {
+      if (pDstMFile->info.size > pDstMFile->info.size) {
+        // Commit succeed, do nothing
+      } else if (pDstMFile->info.size < pDstMFile->info.size) {
+        // Commit failed, back
+        // TODO
+      } else {
+        ASSERT(0);
+      }
+    }
+  } else {
+    tfsremove(&(pSrcMFile->f));
+  }
+
+  return 0;
+}
+
+static int tsdbMakeFSDFileChange(STsdbRepo *pRepo) {
+  STsdbFS *  pFs = REPO_FS(pRepo);
+  int        cidx = 0;
+  int        nidx = 0;
+  SDFileSet *pCSet = NULL;
+  SDFileSet *pNSet = NULL;
+
+  if (cidx < taosArrayGetSize(pFs->curr->df)) {
+    pCSet = taosArrayGet(pFs->curr->df, cidx);
+  } else {
+    pCSet = NULL;
+  }
+
+  if (nidx < taosArrayGetSize(pFs->new->df)) {
+    pNSet = taosArrayGet(pFs->new->df, nidx);
+  } else {
+    pNSet = NULL;
+  }
+
+  while (true) {
+    if (pCSet == NULL && pNSet == NULL) break;
+
+    if (pCSet == NULL || (pNSet != NULL && pCSet->id > pNSet->id)) {
+      tsdbRemoveDFileSet(pNSet);
+
+      nidx++;
+      if (nidx < taosArrayGetSize(pFs->new->df)) {
+        pNSet = taosArrayGet(pFs->new->df, nidx);
+      } else {
+        pNSet = NULL;
+      }
+    } else if (pNSet == NULL || (pCSet != NULL && pCSet->id < pNSet->id)) {
+      cidx++;
+      if (cidx < taosArrayGetSize(pFs->curr->df)) {
+        pCSet = taosArrayGet(pFs->curr->df, cidx);
+      } else {
+        pCSet = NULL;
+      }
+    } else {
+      // TODO: apply dfileset change
+      nidx++;
+      if (nidx < taosArrayGetSize(pFs->new->df)) {
+        pNSet = taosArrayGet(pFs->new->df, nidx);
+      } else {
+        pNSet = NULL;
+      }
+
+      cidx++;
+      if (cidx < taosArrayGetSize(pFs->curr->df)) {
+        pCSet = taosArrayGet(pFs->curr->df, cidx);
+      } else {
+        pCSet = NULL;
+      }
+    }
+  }
+
+  return 0;
+}
\ No newline at end of file

src/tsdb/src/tsdbMain.c

@@ -109,7 +109,7 @@ TSDB_REPO_T *tsdbOpenRepo(char *rootDir, STsdbAppH *pAppH) {
     goto _err;
   }
 
-  if (tsdbOpenFileH(pRepo) < 0) {
+  if (tsdbOpenFS(pRepo) < 0) {
     tsdbError("vgId:%d failed to open file handle since %s", REPO_ID(pRepo), tstrerror(terrno));
     goto _err;
   }