DB option: new option cacheLastRow

src/common/inc/tglobal.h

@@ -94,6 +94,7 @@ extern int32_t tsFsyncPeriod;
 extern int32_t tsReplications;
 extern int32_t tsQuorum;
 extern int32_t tsUpdate;
+extern int32_t tsCacheLastRow;
 
 // balance
 extern int32_t tsEnableBalance;

src/common/src/tglobal.c

@@ -127,6 +127,7 @@ int32_t tsFsyncPeriod   = TSDB_DEFAULT_FSYNC_PERIOD;
 int32_t tsReplications  = TSDB_DEFAULT_DB_REPLICA_OPTION;
 int32_t tsQuorum        = TSDB_DEFAULT_DB_QUORUM_OPTION;
 int32_t tsUpdate        = TSDB_DEFAULT_DB_UPDATE_OPTION;
+int32_t tsCacheLastRow  = TSDB_DEFAULT_CACHE_BLOCK_SIZE;
 int32_t tsMaxVgroupsPerDb  = 0;
 int32_t tsMinTablePerVnode = TSDB_TABLES_STEP;
 int32_t tsMaxTablePerVnode = TSDB_DEFAULT_TABLES;

src/dnode/src/dnodeVMgmt.c

@@ -141,6 +141,7 @@ static SCreateVnodeMsg* dnodeParseVnodeMsg(SRpcMsg *rpcMsg) {
   pCreate->cfg.maxRowsPerFileBlock = htonl(pCreate->cfg.maxRowsPerFileBlock);
   pCreate->cfg.fsyncPeriod         = htonl(pCreate->cfg.fsyncPeriod);
   pCreate->cfg.commitTime          = htonl(pCreate->cfg.commitTime);
+  pCreate->cfg.cacheLastRow        = htonl(pCreate->cfg.cacheLastRow);
 
   for (int32_t j = 0; j < pCreate->cfg.replications; ++j) {
     pCreate->nodes[j].nodeId = htonl(pCreate->nodes[j].nodeId);

src/inc/taosdef.h

@@ -369,6 +369,10 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size, void* buf
 #define TSDB_MAX_DB_UPDATE              1
 #define TSDB_DEFAULT_DB_UPDATE_OPTION   0
 
+#define TSDB_MIN_DB_CACHE_LAST_ROW      0
+#define TSDB_MAX_DB_CACHE_LAST_ROW      1
+#define TSDB_DEFAULT_CACHE_LAST_ROW     0
+
 #define TSDB_MIN_FSYNC_PERIOD           0
 #define TSDB_MAX_FSYNC_PERIOD           180000   // millisecond
 #define TSDB_DEFAULT_FSYNC_PERIOD       3000     // three second

src/inc/taosmsg.h

@@ -548,7 +548,8 @@ typedef struct {
   int8_t   quorum;
   int8_t   ignoreExist;
   int8_t   update;
-  int8_t   reserve[9];
+  int8_t   cacheLastRow;
+  int8_t   reserve[8];
 } SCreateDbMsg, SAlterDbMsg;
 
 typedef struct {
@@ -660,7 +661,8 @@ typedef struct {
   int8_t   wals;
   int8_t   quorum;
   int8_t   update;
-  int8_t   reserved[15];
+  int8_t   cacheLastRow;
+  int8_t   reserved[14];
 } SVnodeCfg;
 
 typedef struct {

src/mnode/inc/mnodeDef.h

@@ -173,7 +173,8 @@ typedef struct {
   int8_t  replications;
   int8_t  quorum;
   int8_t  update;
-  int8_t  reserved[11];
+  int8_t  cacheLastRow;
+  int8_t  reserved[10];
 } SDbCfg;
 
 typedef struct SDbObj {

src/mnode/src/mnodeDb.c

@@ -322,6 +322,11 @@ static int32_t mnodeCheckDbCfg(SDbCfg *pCfg) {
     return TSDB_CODE_MND_INVALID_DB_OPTION;
   }
 
+  if (pCfg->cacheLastRow < TSDB_MIN_DB_CACHE_LAST_ROW || pCfg->cacheLastRow > TSDB_MAX_DB_CACHE_LAST_ROW) {
+    mError("invalid db option cacheLastRow:%d valid range: [%d, %d]", pCfg->cacheLastRow, TSDB_MIN_DB_CACHE_LAST_ROW, TSDB_MAX_DB_CACHE_LAST_ROW);
+    return TSDB_CODE_MND_INVALID_DB_OPTION;
+  }
+
   return TSDB_CODE_SUCCESS;
 }
 
@@ -343,6 +348,7 @@ static void mnodeSetDefaultDbCfg(SDbCfg *pCfg) {
   if (pCfg->replications < 0) pCfg->replications = tsReplications;
   if (pCfg->quorum < 0) pCfg->quorum = tsQuorum;
   if (pCfg->update < 0) pCfg->update = tsUpdate;
+  if (pCfg->cacheLastRow < 0) pCfg->cacheLastRow = tsCacheLastRow;
 }
 
 static int32_t mnodeCreateDbCb(SMnodeMsg *pMsg, int32_t code) {
@@ -396,7 +402,8 @@ static int32_t mnodeCreateDb(SAcctObj *pAcct, SCreateDbMsg *pCreate, SMnodeMsg *
     .walLevel            = pCreate->walLevel,
     .replications        = pCreate->replications,
     .quorum              = pCreate->quorum,
-    .update              = pCreate->update
+    .update              = pCreate->update,
+    .cacheLastRow        = pCreate->cacheLastRow
   };
 
   mnodeSetDefaultDbCfg(&pDb->cfg);
@@ -750,6 +757,10 @@ static int32_t mnodeRetrieveDbs(SShowObj *pShow, char *data, int32_t rows, void
       pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
       *(int8_t *)pWrite = pDb->cfg.compression;
       cols++;
+
+      pWrite = data + pShow->offset[cols] * rows + pShow->bytes[cols] * numOfRows;
+      *(int8_t *)pWrite = pDb->cfg.cacheLastRow;
+      cols++;
 #ifndef __CLOUD_VERSION__
     }
 #endif
@@ -864,6 +875,7 @@ static SDbCfg mnodeGetAlterDbOption(SDbObj *pDb, SAlterDbMsg *pAlter) {
   int8_t  quorum         = pAlter->quorum;
   int8_t  precision      = pAlter->precision;
   int8_t  update         = pAlter->update;
+  int8_t  cacheLastRow   = pAlter->cacheLastRow;
   
   terrno = TSDB_CODE_SUCCESS;
 
@@ -976,6 +988,11 @@ static SDbCfg mnodeGetAlterDbOption(SDbObj *pDb, SAlterDbMsg *pAlter) {
 #endif
   }
 
+  if (cacheLastRow >= 0 && cacheLastRow != pDb->cfg.cacheLastRow) {
+    mDebug("db:%s, cacheLastRow:%d change to %d", pDb->name, pDb->cfg.cacheLastRow, cacheLastRow);
+    newCfg.cacheLastRow = cacheLastRow;
+  }
+
   return newCfg;
 }
 

src/mnode/src/mnodeVgroup.c

@@ -859,6 +859,7 @@ static SCreateVnodeMsg *mnodeBuildVnodeMsg(SVgObj *pVgroup) {
   pCfg->wals                = 3;
   pCfg->quorum              = pDb->cfg.quorum;
   pCfg->update              = pDb->cfg.update;
+  pCfg->cacheLastRow        = pDb->cfg.cacheLastRow;
   
   SVnodeDesc *pNodes = pVnode->nodes;
   for (int32_t j = 0; j < pVgroup->numOfVnodes; ++j) {

src/vnode/src/vnodeCfg.c

@@ -33,6 +33,7 @@ static void vnodeLoadCfg(SVnodeObj *pVnode, SCreateVnodeMsg* vnodeMsg) {
   pVnode->tsdbCfg.maxRowsPerFileBlock = vnodeMsg->cfg.maxRowsPerFileBlock;
   pVnode->tsdbCfg.precision = vnodeMsg->cfg.precision;
   pVnode->tsdbCfg.compression = vnodeMsg->cfg.compression;
+  pVnode->tsdbCfg.cacheLastRow = vnodeMsg->cfg.cacheLastRow;
   pVnode->walCfg.walLevel = vnodeMsg->cfg.walLevel;
   pVnode->walCfg.fsyncPeriod = vnodeMsg->cfg.fsyncPeriod;
   pVnode->walCfg.keep = TAOS_WAL_NOT_KEEP;
@@ -207,6 +208,13 @@ int32_t vnodeReadCfg(SVnodeObj *pVnode) {
   }
   vnodeMsg.cfg.quorum = (int8_t)quorum->valueint;
 
+  cJSON *cacheLastRow = cJSON_GetObjectItem(root, "cacheLastRow");
+  if (!cacheLastRow || cacheLastRow->type != cJSON_Number) {
+    vError("vgId: %d, failed to read %s, cacheLastRow not found", pVnode->vgId, file);
+    goto PARSE_VCFG_ERROR;
+  }
+  vnodeMsg.cfg.cacheLastRow = (int8_t)cacheLastRow->valueint;
+
   cJSON *nodeInfos = cJSON_GetObjectItem(root, "nodeInfos");
   if (!nodeInfos || nodeInfos->type != cJSON_Array) {
     vError("vgId:%d, failed to read %s, nodeInfos not found", pVnode->vgId, file);
@@ -294,6 +302,7 @@ int32_t vnodeWriteCfg(SCreateVnodeMsg *pMsg) {
   len += snprintf(content + len, maxLen - len, "  \"replica\": %d,\n", pMsg->cfg.replications);
   len += snprintf(content + len, maxLen - len, "  \"wals\": %d,\n", pMsg->cfg.wals);
   len += snprintf(content + len, maxLen - len, "  \"quorum\": %d,\n", pMsg->cfg.quorum);
+  len += snprintf(content + len, maxLen - len, "  \"cacheLastRow\": %d,\n", pMsg->cfg.cacheLastRow);
   len += snprintf(content + len, maxLen - len, "  \"nodeInfos\": [{\n");
   for (int32_t i = 0; i < pMsg->cfg.replications; i++) {
     SVnodeDesc *node = &pMsg->nodes[i];

src/vnode/src/vnodeMain.c

@@ -86,6 +86,7 @@ int32_t vnodeCreate(SCreateVnodeMsg *pVnodeCfg) {
   tsdbCfg.precision           = pVnodeCfg->cfg.precision;
   tsdbCfg.compression         = pVnodeCfg->cfg.compression;
   tsdbCfg.update              = pVnodeCfg->cfg.update;
+  tsdbCfg.cacheLastRow        = pVnodeCfg->cfg.cacheLastRow;
 
   char tsdbDir[TSDB_FILENAME_LEN] = {0};
   sprintf(tsdbDir, "%s/vnode%d/tsdb", tsVnodeDir, pVnodeCfg->cfg.vgId);