enh(query): add cache for table meta.

source/libs/executor/inc/executorimpl.h

@@ -298,6 +298,12 @@ typedef struct {
   SExprSupp*     pExprSup;  // expr supporter of aggregate operator
 } SAggOptrPushDownInfo;
 
+typedef struct STableMetaCacheInfo {
+  SLRUCache*             pTableMetaEntryCache; // 100 by default
+  uint64_t               metaFetch;
+  uint64_t               cacheHit;
+} STableMetaCacheInfo;
+
 typedef struct STableScanInfo {
   STsdbReader*           dataReader;
   SReadHandle            readHandle;
@@ -318,7 +324,7 @@ typedef struct STableScanInfo {
   int8_t                 scanMode;
   SAggOptrPushDownInfo   pdInfo;
   int8_t                 assignBlockUid;
-  SLRUCache*             pTableMetaEntryCache; // 100 by default
+  STableMetaCacheInfo    metaCache;
 } STableScanInfo;
 
 typedef struct STableMergeScanInfo {
@@ -327,7 +333,6 @@ typedef struct STableMergeScanInfo {
   int32_t                tableEndIndex;
   bool                   hasGroupId;
   uint64_t               groupId;
-  SArray*                dataReaders;  // array of tsdbReaderT*
   SArray*                queryConds;   // array of queryTableDataCond
   STsdbReader*           pReader;
   SReadHandle            readHandle;
@@ -898,7 +903,7 @@ int32_t getBufferPgSize(int32_t rowSize, uint32_t* defaultPgsz, uint32_t* defaul
 void    doSetOperatorCompleted(SOperatorInfo* pOperator);
 void    doFilter(const SNode* pFilterNode, SSDataBlock* pBlock, SColMatchInfo* pColMatchInfo, SFilterInfo* pFilterInfo);
 int32_t addTagPseudoColumnData(SReadHandle* pHandle, const SExprInfo* pExpr, int32_t numOfExpr,
-                               SSDataBlock* pBlock, int32_t rows, const char* idStr, SLRUCache* pCache);
+                               SSDataBlock* pBlock, int32_t rows, const char* idStr, STableMetaCacheInfo * pCache);
 
 void cleanupAggSup(SAggSupporter* pAggSup);
 void appendOneRowToDataBlock(SSDataBlock* pBlock, STupleHandle* pTupleHandle);

source/libs/executor/src/cachescanoperator.c

@@ -172,7 +172,7 @@ SSDataBlock* doScanCache(SOperatorInfo* pOperator) {
 
       SExprSupp* pSup = &pInfo->pseudoExprSup;
       int32_t code = addTagPseudoColumnData(&pInfo->readHandle, pSup->pExprInfo, pSup->numOfExprs, pRes,
-                                            pRes->info.rows, GET_TASKID(pTaskInfo));
+                                            pRes->info.rows, GET_TASKID(pTaskInfo), NULL);
       if (code != TSDB_CODE_SUCCESS) {
         pTaskInfo->code = code;
         return NULL;
@@ -221,7 +221,7 @@ SSDataBlock* doScanCache(SOperatorInfo* pOperator) {
 
             pInfo->pRes->info.uid = *(tb_uid_t*)taosArrayGet(pInfo->pUidList, 0);
             code = addTagPseudoColumnData(&pInfo->readHandle, pSup->pExprInfo, pSup->numOfExprs, pInfo->pRes, pInfo->pRes->info.rows,
-                                          GET_TASKID(pTaskInfo));
+                                          GET_TASKID(pTaskInfo), NULL);
             if (code != TSDB_CODE_SUCCESS) {
               pTaskInfo->code = code;
               return NULL;

source/libs/executor/src/scanoperator.c

@@ -13,6 +13,7 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <vnode.h>
 #include "executorimpl.h"
 #include "filter.h"
 #include "function.h"
@@ -339,7 +340,7 @@ static void doSetTagColumnData(STableScanInfo* pTableScanInfo, SSDataBlock* pBlo
     SExprSupp* pSup = &pTableScanInfo->pseudoSup;
 
     int32_t code = addTagPseudoColumnData(&pTableScanInfo->readHandle, pSup->pExprInfo, pSup->numOfExprs, pBlock, rows,
-                                          GET_TASKID(pTaskInfo));
+                                          GET_TASKID(pTaskInfo), &pTableScanInfo->metaCache);
     if (code != TSDB_CODE_SUCCESS) {
       T_LONG_JMP(pTaskInfo->env, code);
     }
@@ -505,8 +506,25 @@ typedef struct STableCachedVal {
   STag* pTags;
 } STableCachedVal;
 
+static void freeTableCachedVal(void* param) {
+  if (param == NULL) {
+    return;
+  }
+
+  STableCachedVal* pVal = param;
+  taosMemoryFree((void*)pVal->pName);
+  taosMemoryFree(pVal->pTags);
+  taosMemoryFree(pVal);
+}
+
+//const void *key, size_t keyLen, void *value
+static void freeCachedMetaItem(const void *key, size_t keyLen, void *value) {
+  taosMemoryFree((void*)key);
+  freeTableCachedVal(value);
+}
+
 int32_t addTagPseudoColumnData(SReadHandle* pHandle, const SExprInfo* pExpr, int32_t numOfExpr,
-                               SSDataBlock* pBlock, int32_t rows, const char* idStr, SLRUCache* pCache) {
+                               SSDataBlock* pBlock, int32_t rows, const char* idStr, STableMetaCacheInfo* pCache) {
   // currently only the tbname pseudo column
   if (numOfExpr <= 0) {
     return TSDB_CODE_SUCCESS;
@@ -518,13 +536,13 @@ int32_t addTagPseudoColumnData(SReadHandle* pHandle, const SExprInfo* pExpr, int
   int32_t backupRows = pBlock->info.rows;
   pBlock->info.rows = rows;
 
+  bool freeReader = false;
   STableCachedVal val = {0};
-  bool needFreeReader = true;
 
-  // 1. check if it is existed in meta cache
-  LRUHandle *h = taosLRUCacheLookup(pCache, &pBlock->info.uid, sizeof(pBlock->info.uid));
-  if (h == NULL) {
   SMetaReader mr = {0};
+
+  // 1. check if it is existed in meta cache
+  if (pCache == NULL) {
     metaReaderInit(&mr, pHandle->meta, 0);
     code = metaGetTableEntryByUid(&mr, pBlock->info.uid);
     if (code != TSDB_CODE_SUCCESS) {
@@ -534,12 +552,47 @@ int32_t addTagPseudoColumnData(SReadHandle* pHandle, const SExprInfo* pExpr, int
     }
 
     metaReaderReleaseLock(&mr);
+
     val.pName = mr.me.name;
     val.pTags = (STag*)mr.me.ctbEntry.pTags;
+
+    freeReader = true;
+  } else {
+    pCache->metaFetch += 1;
+
+    LRUHandle* h = taosLRUCacheLookup(pCache->pTableMetaEntryCache, &pBlock->info.uid, sizeof(pBlock->info.uid));
+    if (h == NULL) {
+      metaReaderInit(&mr, pHandle->meta, 0);
+      code = metaGetTableEntryByUid(&mr, pBlock->info.uid);
+      if (code != TSDB_CODE_SUCCESS) {
+        qError("failed to get table meta, uid:0x%" PRIx64 ", code:%s, %s", pBlock->info.uid, tstrerror(terrno), idStr);
+        metaReaderClear(&mr);
+        return terrno;
+      }
+
+      metaReaderReleaseLock(&mr);
+
+      STableCachedVal* pVal = taosMemoryMalloc(sizeof(STableCachedVal));
+      pVal->pName = strdup(mr.me.name);
+      STag* pTag = (STag*)mr.me.ctbEntry.pTags;
+
+      pVal->pTags = taosMemoryMalloc(pTag->len);
+      memcpy(pVal->pTags, mr.me.ctbEntry.pTags, pTag->len);
+
+      freeReader = true;
+      int32_t ret = taosLRUCacheInsert(pCache->pTableMetaEntryCache, &pBlock->info.uid, sizeof(uint64_t), pVal, sizeof(STableCachedVal), freeCachedMetaItem, NULL, TAOS_LRU_PRIORITY_LOW);
+      if (ret != TAOS_LRU_STATUS_OK) {
+        qError("failed to put meta into lru cache, code:%d, %s", ret, idStr);
+        freeTableCachedVal(pVal);
       } else {
-    STableCachedVal* pVal = taosLRUCacheValue(pCache, h);
         val = *pVal;
       }
+    } else {
+      pCache->cacheHit += 1;
+      STableCachedVal* pVal = taosLRUCacheValue(pCache->pTableMetaEntryCache, h);
+      val = *pVal;
+    }
+  }
 
   for (int32_t j = 0; j < numOfExpr; ++j) {
     const SExprInfo* pExpr1 = &pExpr[j];
@@ -581,10 +634,12 @@ int32_t addTagPseudoColumnData(SReadHandle* pHandle, const SExprInfo* pExpr, int
     }
   }
 
-  metaReaderClear(&mr);
-
   // restore the rows
   pBlock->info.rows = backupRows;
+  if (freeReader) {
+    metaReaderClear(&mr);
+  }
+
   return TSDB_CODE_SUCCESS;
 }
 
@@ -832,6 +887,7 @@ static void destroyTableScanOperatorInfo(void* param) {
     taosArrayDestroy(pTableScanInfo->matchInfo.pList);
   }
 
+  taosLRUCacheCleanup(pTableScanInfo->metaCache.pTableMetaEntryCache);
   cleanupExprSupp(&pTableScanInfo->pseudoSup);
   taosMemoryFreeClear(param);
 }
@@ -898,7 +954,7 @@ SOperatorInfo* createTableScanOperatorInfo(STableScanPhysiNode* pTableScanNode,
   pOperator->exprSupp.numOfExprs = numOfCols;
   pOperator->pTaskInfo = pTaskInfo;
 
-  pInfo->pTableMetaEntryCache = taosLRUCacheInit(100, -1, .5);
+  pInfo->metaCache.pTableMetaEntryCache = taosLRUCacheInit(100, -1, .5);
 
   pOperator->fpSet = createOperatorFpSet(operatorDummyOpenFn, doTableScan, NULL, NULL, destroyTableScanOperatorInfo,
                                          getTableScannerExecInfo);
@@ -1650,7 +1706,7 @@ static int32_t setBlockIntoRes(SStreamScanInfo* pInfo, const SSDataBlock* pBlock
   // currently only the tbname pseudo column
   if (pInfo->numOfPseudoExpr > 0) {
     int32_t code = addTagPseudoColumnData(&pInfo->readHandle, pInfo->pPseudoExpr, pInfo->numOfPseudoExpr, pInfo->pRes,
-                                          pInfo->pRes->info.rows, GET_TASKID(pTaskInfo));
+                                          pInfo->pRes->info.rows, GET_TASKID(pTaskInfo), NULL);
     if (code != TSDB_CODE_SUCCESS) {
       blockDataFreeRes((SSDataBlock*)pBlock);
       T_LONG_JMP(pTaskInfo->env, code);
@@ -4380,7 +4436,7 @@ static int32_t loadDataBlockFromOneTable(SOperatorInfo* pOperator, STableMergeSc
   SExprSupp* pSup = &pTableScanInfo->pseudoSup;
 
   int32_t code = addTagPseudoColumnData(&pTableScanInfo->readHandle, pSup->pExprInfo, pSup->numOfExprs, pBlock,
-                                        pBlock->info.rows, GET_TASKID(pTaskInfo));
+                                        pBlock->info.rows, GET_TASKID(pTaskInfo), NULL);
   if (code != TSDB_CODE_SUCCESS) {
     T_LONG_JMP(pTaskInfo->env, code);
   }