refactor: do some internal refactor optimize the building block performance.

source/dnode/vnode/src/tsdb/tsdbRead.c

@@ -152,7 +152,7 @@ static void     updateSchema(TSDBROW* pRow, uint64_t uid, STsdbReader* pReader);
 static bool     hasBeenDropped(const SArray* pDelList, int32_t* index, TSDBKEY* pKey, int32_t order);
 
 static void doMergeMultiRows(TSDBROW* pRow, uint64_t uid, SIterInfo* pIter, SArray* pDelList, STSRow** pTSRow,
-                             STsdbReader* pReader);
+                             STsdbReader* pReader, bool* freeTSRow);
 static void doMergeMemIMemRows(TSDBROW* pRow, TSDBROW* piRow, STableBlockScanInfo* pBlockScanInfo, STsdbReader* pReader,
                                STSRow** pTSRow);
 static int32_t initDelSkylineIterator(STableBlockScanInfo* pBlockScanInfo, STsdbReader* pReader, STbData* pMemTbData,
@@ -1235,6 +1235,7 @@ static int32_t doMergeBufAndFileRows(STsdbReader* pReader, STableBlockScanInfo*
   TSDBKEY k = TSDBROW_KEY(pRow);
   TSDBROW fRow = tsdbRowFromBlockData(pBlockData, pDumpInfo->rowIndex);
   SArray* pDelList = pBlockScanInfo->delSkyline;
+  bool freeTSRow = false;
 
   // ascending order traverse
   if (ASCENDING_TRAVERSE(pReader->order)) {
@@ -1248,7 +1249,7 @@ static int32_t doMergeBufAndFileRows(STsdbReader* pReader, STableBlockScanInfo*
         tRowMergerGetRow(&merge, &pTSRow);
       }
     } else if (k.ts < key) {  // k.ts < key
-      doMergeMultiRows(pRow, pBlockScanInfo->uid, pIter, pDelList, &pTSRow, pReader);
+      doMergeMultiRows(pRow, pBlockScanInfo->uid, pIter, pDelList, &pTSRow, pReader, &freeTSRow);
     } else {  // k.ts == key, ascending order: file block ----> imem rows -----> mem rows
       tRowMergerInit(&merge, &fRow, pReader->pSchema);
       doMergeRowsInFileBlocks(pBlockData, pBlockScanInfo, pReader, &merge);
@@ -1260,7 +1261,7 @@ static int32_t doMergeBufAndFileRows(STsdbReader* pReader, STableBlockScanInfo*
     }
   } else {  // descending order scan
     if (key < k.ts) {
-      doMergeMultiRows(pRow, pBlockScanInfo->uid, pIter, pDelList, &pTSRow, pReader);
+      doMergeMultiRows(pRow, pBlockScanInfo->uid, pIter, pDelList, &pTSRow, pReader, &freeTSRow);
     } else if (k.ts < key) {
       if (tryCopyDistinctRowFromFileBlock(pReader, pBlockData, key, pDumpInfo)) {
         return TSDB_CODE_SUCCESS;
@@ -1302,12 +1303,12 @@ static int32_t doMergeThreeLevelRows(STsdbReader* pReader, STableBlockScanInfo*
   ASSERT(pRow != NULL && piRow != NULL);
 
   int64_t key = pBlockData->aTSKEY[pDumpInfo->rowIndex];
+  bool    freeTSRow = false;
 
   uint64_t uid = pBlockScanInfo->uid;
 
   TSDBKEY k = TSDBROW_KEY(pRow);
   TSDBKEY ik = TSDBROW_KEY(piRow);
-
   if (ASCENDING_TRAVERSE(pReader->order)) {
     // [1&2] key <= [k.ts && ik.ts]
     if (key <= k.ts && key <= ik.ts) {
@@ -1335,16 +1336,22 @@ static int32_t doMergeThreeLevelRows(STsdbReader* pReader, STableBlockScanInfo*
       // [3] ik.ts < key <= k.ts
       // [4] ik.ts < k.ts <= key
       if (ik.ts < k.ts) {
-        doMergeMultiRows(piRow, uid, &pBlockScanInfo->iiter, pDelList, &pTSRow, pReader);
+        doMergeMultiRows(piRow, uid, &pBlockScanInfo->iiter, pDelList, &pTSRow, pReader, &freeTSRow);
         doAppendRowFromTSRow(pReader->pResBlock, pReader, pTSRow);
+        if (freeTSRow) {
+          taosMemoryFree(pTSRow);
+        }
         return TSDB_CODE_SUCCESS;
       }
 
       // [5] k.ts < key   <= ik.ts
       // [6] k.ts < ik.ts <= key
       if (k.ts < ik.ts) {
-        doMergeMultiRows(pRow, uid, &pBlockScanInfo->iter, pDelList, &pTSRow, pReader);
+        doMergeMultiRows(pRow, uid, &pBlockScanInfo->iter, pDelList, &pTSRow, pReader, &freeTSRow);
         doAppendRowFromTSRow(pReader->pResBlock, pReader, pTSRow);
+        if (freeTSRow) {
+          taosMemoryFree(pTSRow);
+        }
         return TSDB_CODE_SUCCESS;
       }
 
@@ -1354,6 +1361,7 @@ static int32_t doMergeThreeLevelRows(STsdbReader* pReader, STableBlockScanInfo*
 
         doMergeMemIMemRows(pRow, piRow, pBlockScanInfo, pReader, &pTSRow);
         doAppendRowFromTSRow(pReader->pResBlock, pReader, pTSRow);
+        taosMemoryFree(pTSRow);
         return TSDB_CODE_SUCCESS;
       }
     }
@@ -1385,8 +1393,11 @@ static int32_t doMergeThreeLevelRows(STsdbReader* pReader, STableBlockScanInfo*
       // [3] ik.ts > k.ts >= Key
       // [4] ik.ts > key >= k.ts
       if (ik.ts > key) {
-        doMergeMultiRows(piRow, uid, &pBlockScanInfo->iiter, pDelList, &pTSRow, pReader);
+        doMergeMultiRows(piRow, uid, &pBlockScanInfo->iiter, pDelList, &pTSRow, pReader, &freeTSRow);
         doAppendRowFromTSRow(pReader->pResBlock, pReader, pTSRow);
+        if (freeTSRow) {
+          taosMemoryFree(pTSRow);
+        }
         return TSDB_CODE_SUCCESS;
       }
 
@@ -1399,18 +1410,21 @@ static int32_t doMergeThreeLevelRows(STsdbReader* pReader, STableBlockScanInfo*
         doMergeRowsInFileBlocks(pBlockData, pBlockScanInfo, pReader, &merge);
         tRowMergerGetRow(&merge, &pTSRow);
         doAppendRowFromTSRow(pReader->pResBlock, pReader, pTSRow);
+        taosMemoryFree(pTSRow);
         return TSDB_CODE_SUCCESS;
       }
 
       //[7] key = ik.ts > k.ts
       if (key == ik.ts) {
-        doMergeMultiRows(piRow, uid, &pBlockScanInfo->iiter, pDelList, &pTSRow, pReader);
+        doMergeMultiRows(piRow, uid, &pBlockScanInfo->iiter, pDelList, &pTSRow, pReader, &freeTSRow);
 
         TSDBROW fRow = tsdbRowFromBlockData(pBlockData, pDumpInfo->rowIndex);
         tRowMerge(&merge, &fRow);
         doMergeRowsInFileBlocks(pBlockData, pBlockScanInfo, pReader, &merge);
         tRowMergerGetRow(&merge, &pTSRow);
         doAppendRowFromTSRow(pReader->pResBlock, pReader, pTSRow);
+
+        taosMemoryFree(pTSRow);
         return TSDB_CODE_SUCCESS;
       }
     }
@@ -2280,11 +2294,29 @@ void updateSchema(TSDBROW* pRow, uint64_t uid, STsdbReader* pReader) {
 }
 
 void doMergeMultiRows(TSDBROW* pRow, uint64_t uid, SIterInfo* pIter, SArray* pDelList, STSRow** pTSRow,
-                      STsdbReader* pReader) {
+                      STsdbReader* pReader, bool* freeTSRow) {
+  {  // if the timestamp of the next valid row has a different ts, return current row directly
+    TSDBROW current = *pRow;
+    pIter->hasVal = tsdbTbDataIterNext(pIter->iter);
+
+    if (!pIter->hasVal) {
+      *pTSRow = current.pTSRow;
+      *freeTSRow = false;
+      return;
+    } else {  // has next point in mem/imem
+      TSDBROW* pNextRow = getValidRow(pIter, pDelList, pReader);
+      if (TSDBROW_KEY(&current).ts != TSDBROW_KEY(pNextRow).ts) {
+        *pTSRow = current.pTSRow;
+        *freeTSRow = false;
+        return;
+      }
+    }
+  }
+
   SRowMerger merge = {0};
+  TSDBKEY    k = TSDBROW_KEY(pRow);
 
-  TSDBKEY k = TSDBROW_KEY(pRow);
-  // updateSchema(pRow, uid, pReader);
+  // get the correct schema for data in memory
   int32_t   sversion = TSDBROW_SVERSION(pRow);
   STSchema* pTSchema = NULL;
   if (sversion != pReader->pSchema->version) {
@@ -2298,6 +2330,8 @@ void doMergeMultiRows(TSDBROW* pRow, uint64_t uid, SIterInfo* pIter, SArray* pDe
   tRowMergerGetRow(&merge, pTSRow);
   tRowMergerClear(&merge);
 
+  *freeTSRow = true;
+
   if (sversion != pReader->pSchema->version) {
     taosMemoryFree(pTSchema);
   }
@@ -2332,7 +2366,7 @@ void doMergeMemIMemRows(TSDBROW* pRow, TSDBROW* piRow, STableBlockScanInfo* pBlo
 }
 
 int32_t tsdbGetNextRowInMem(STableBlockScanInfo* pBlockScanInfo, STsdbReader* pReader, STSRow** pTSRow,
-                            int64_t endKey) {
+                            int64_t endKey, bool* freeTSRow) {
   TSDBROW* pRow = getValidRow(&pBlockScanInfo->iter, pBlockScanInfo->delSkyline, pReader);
   TSDBROW* piRow = getValidRow(&pBlockScanInfo->iiter, pBlockScanInfo->delSkyline, pReader);
   SArray*  pDelList = pBlockScanInfo->delSkyline;
@@ -2358,23 +2392,24 @@ int32_t tsdbGetNextRowInMem(STableBlockScanInfo* pBlockScanInfo, STsdbReader* pR
     TSDBKEY ik = TSDBROW_KEY(piRow);
 
     if (ik.ts < k.ts) {  // ik.ts < k.ts
-      doMergeMultiRows(piRow, pBlockScanInfo->uid, &pBlockScanInfo->iiter, pDelList, pTSRow, pReader);
+      doMergeMultiRows(piRow, pBlockScanInfo->uid, &pBlockScanInfo->iiter, pDelList, pTSRow, pReader, freeTSRow);
     } else if (k.ts < ik.ts) {
-      doMergeMultiRows(pRow, pBlockScanInfo->uid, &pBlockScanInfo->iter, pDelList, pTSRow, pReader);
+      doMergeMultiRows(pRow, pBlockScanInfo->uid, &pBlockScanInfo->iter, pDelList, pTSRow, pReader, freeTSRow);
     } else {  // ik.ts == k.ts
       doMergeMemIMemRows(pRow, piRow, pBlockScanInfo, pReader, pTSRow);
+      *freeTSRow = true;
     }
 
     return TSDB_CODE_SUCCESS;
   }
 
   if (pBlockScanInfo->iter.hasVal && pRow != NULL) {
-    doMergeMultiRows(pRow, pBlockScanInfo->uid, &pBlockScanInfo->iter, pDelList, pTSRow, pReader);
+    doMergeMultiRows(pRow, pBlockScanInfo->uid, &pBlockScanInfo->iter, pDelList, pTSRow, pReader, freeTSRow);
     return TSDB_CODE_SUCCESS;
   }
 
   if (pBlockScanInfo->iiter.hasVal && piRow != NULL) {
-    doMergeMultiRows(piRow, pBlockScanInfo->uid, &pBlockScanInfo->iiter, pDelList, pTSRow, pReader);
+    doMergeMultiRows(piRow, pBlockScanInfo->uid, &pBlockScanInfo->iiter, pDelList, pTSRow, pReader, freeTSRow);
     return TSDB_CODE_SUCCESS;
   }
 
@@ -2472,13 +2507,16 @@ int32_t buildDataBlockFromBufImpl(STableBlockScanInfo* pBlockScanInfo, int64_t e
 
   do {
     STSRow* pTSRow = NULL;
-    tsdbGetNextRowInMem(pBlockScanInfo, pReader, &pTSRow, endKey);
+    bool freeTSRow = false;
+    tsdbGetNextRowInMem(pBlockScanInfo, pReader, &pTSRow, endKey, &freeTSRow);
     if (pTSRow == NULL) {
       break;
     }
 
     doAppendRowFromTSRow(pBlock, pReader, pTSRow);
-    taosMemoryFree(pTSRow);
+    if (freeTSRow) {
+      taosMemoryFree(pTSRow);
+    }
 
     // no data in buffer, return immediately
     if (!(pBlockScanInfo->iter.hasVal || pBlockScanInfo->iiter.hasVal)) {