Merge pull request #7376 from taosdata/feature/TD-5623

[TD-5623]<feature>: add retrieved column data compression mechanism

src/client/src/tscServer.c

@@ -2678,6 +2678,50 @@ int tscProcessQueryRsp(SSqlObj *pSql) {
   return 0;
 }
 
+static void decompressQueryColData(SSqlRes *pRes, SQueryInfo* pQueryInfo, char **data, int8_t compressed, int compLen) {
+  int32_t decompLen = 0;
+  int32_t numOfCols = pQueryInfo->fieldsInfo.numOfOutput;
+  int32_t *compSizes;
+  char    *pData = *data;
+  compSizes = (int32_t *)(pData + compLen);
+
+  TAOS_FIELD *pField = tscFieldInfoGetField(&pQueryInfo->fieldsInfo, numOfCols - 1);
+  int16_t     offset = tscFieldInfoGetOffset(pQueryInfo, numOfCols - 1);
+  char       *outputBuf = tcalloc(pRes->numOfRows, (pField->bytes + offset));
+
+  char *p = outputBuf;
+  int32_t bufOffset;
+  for (int32_t i = 0; i < numOfCols; ++i) {
+    SInternalField* pInfo = (SInternalField*)TARRAY_GET_ELEM(pQueryInfo->fieldsInfo.internalField, i);
+    bufOffset = pInfo->field.bytes * pRes->numOfRows;
+
+    int32_t flen = (*(tDataTypes[pInfo->field.type].decompFunc))(pData, htonl(compSizes[i]), pRes->numOfRows, p, bufOffset,
+                                                               compressed, NULL, 0);
+
+    p += flen;
+    decompLen +=flen;
+    pData += htonl(compSizes[i]);
+  }
+
+  /* Resize rsp as decompressed data will occupy more space */
+  pRes->rspLen = pRes->rspLen - (compLen + numOfCols * sizeof(int32_t)) + decompLen;
+  char *new_rsp = (char *)realloc(pRes->pRsp, pRes->rspLen);
+  if (new_rsp == NULL) {
+    pRes->code = TSDB_CODE_TSC_OUT_OF_MEMORY;
+    return;
+  } else {
+    pRes->pRsp = new_rsp;
+    *data = ((SRetrieveTableRsp *)pRes->pRsp)->data;
+    pData = *data + compLen + numOfCols * sizeof(int32_t);
+  }
+
+  int32_t tailLen = pRes->rspLen - sizeof(SRetrieveTableRsp) - decompLen;
+  memmove(*data + decompLen, pData, tailLen);
+  memmove(*data, outputBuf, decompLen);
+
+  tfree(outputBuf);
+}
+
 int tscProcessRetrieveRspFromNode(SSqlObj *pSql) {
   SSqlRes *pRes = &pSql->res;
   SSqlCmd *pCmd = &pSql->cmd;
@@ -2690,18 +2734,24 @@ int tscProcessRetrieveRspFromNode(SSqlObj *pSql) {
     return pRes->code;
   }
 
-  pRes->numOfRows = htonl(pRetrieve->numOfRows);
+  pRes->numOfRows  = htonl(pRetrieve->numOfRows);
-  pRes->precision = htons(pRetrieve->precision);
+  pRes->precision  = htons(pRetrieve->precision);
-  pRes->offset    = htobe64(pRetrieve->offset);
+  pRes->offset     = htobe64(pRetrieve->offset);
-  pRes->useconds  = htobe64(pRetrieve->useconds);
+  pRes->useconds   = htobe64(pRetrieve->useconds);
-  pRes->completed = (pRetrieve->completed == 1);
+  pRes->completed  = (pRetrieve->completed == 1);
-  pRes->data      = pRetrieve->data;
+  pRes->data       = pRetrieve->data;
-  
+
   SQueryInfo* pQueryInfo = tscGetQueryInfo(pCmd);
   if (tscCreateResPointerInfo(pRes, pQueryInfo) != TSDB_CODE_SUCCESS) {
     return pRes->code;
   }
 
+  //Decompress col data if compressed from server
+  if (pRetrieve->compressed) {
+    int32_t compLen = htonl(pRetrieve->compLen);
+    decompressQueryColData(pRes, pQueryInfo, &pRes->data, pRetrieve->compressed, compLen);
+  }
+
   STableMetaInfo *pTableMetaInfo = tscGetMetaInfo(pQueryInfo, 0);
   if ((pCmd->command == TSDB_SQL_RETRIEVE) ||
       ((UTIL_TABLE_IS_CHILD_TABLE(pTableMetaInfo) || UTIL_TABLE_IS_NORMAL_TABLE(pTableMetaInfo)) &&
@@ -2714,10 +2764,10 @@ int tscProcessRetrieveRspFromNode(SSqlObj *pSql) {
 
   if (pSql->pSubscription != NULL) {
     int32_t numOfCols = pQueryInfo->fieldsInfo.numOfOutput;
-    
+
     TAOS_FIELD *pField = tscFieldInfoGetField(&pQueryInfo->fieldsInfo, numOfCols - 1);
     int16_t     offset = tscFieldInfoGetOffset(pQueryInfo, numOfCols - 1);
-    
+
     char* p = pRes->data + (pField->bytes + offset) * pRes->numOfRows;
 
     int32_t numOfTables = htonl(*(int32_t*)p);

src/common/inc/tglobal.h

@@ -60,6 +60,7 @@ extern char     tsLocale[];
 extern char     tsCharset[];            // default encode string
 extern int8_t   tsEnableCoreFile;
 extern int32_t  tsCompressMsgSize;
+extern int32_t  tsCompressColData;
 extern int32_t  tsMaxNumOfDistinctResults;
 extern char     tsTempDir[];
 

src/common/src/tglobal.c

@@ -75,6 +75,14 @@ int32_t tsMaxBinaryDisplayWidth = 30;
  */
 int32_t tsCompressMsgSize = -1;
 
+/* denote if server needs to compress the retrieved column data before adding to the rpc response message body.
+ * 0: disable column data compression
+ * 1: enable  column data compression
+ * This option is default to disabled. Once enabled, compression will be conducted if any column has size more
+ * than QUERY_COMP_THRESHOLD. Otherwise, no further compression is needed.
+ */
+int32_t tsCompressColData = 0;
+
 // client
 int32_t tsMaxSQLStringLen = TSDB_MAX_ALLOWED_SQL_LEN;
 int32_t tsMaxWildCardsLen = TSDB_PATTERN_STRING_MAX_LEN;
@@ -991,6 +999,16 @@ static void doInitGlobalConfig(void) {
   cfg.unitType = TAOS_CFG_UTYPE_NONE;
   taosInitConfigOption(cfg);
 
+  cfg.option = "compressColData";
+  cfg.ptr = &tsCompressColData;
+  cfg.valType = TAOS_CFG_VTYPE_INT8;
+  cfg.cfgType = TSDB_CFG_CTYPE_B_CONFIG | TSDB_CFG_CTYPE_B_SHOW;
+  cfg.minValue = 0;
+  cfg.maxValue = 1;
+  cfg.ptrLength = 0;
+  cfg.unitType = TAOS_CFG_UTYPE_NONE;
+  taosInitConfigOption(cfg);
+
   cfg.option = "maxSQLLength";
   cfg.ptr = &tsMaxSQLStringLen;
   cfg.valType = TAOS_CFG_VTYPE_INT32;

src/inc/taosmsg.h

@@ -536,6 +536,8 @@ typedef struct SRetrieveTableRsp {
   int16_t precision;
   int64_t offset;     // updated offset value for multi-vnode projection query
   int64_t useconds;
+  int8_t  compressed;
+  int32_t compLen;
   char    data[];
 } SRetrieveTableRsp;
 

src/query/inc/qExecutor.h

@@ -43,6 +43,10 @@ typedef int32_t (*__block_search_fn_t)(char* data, int32_t num, int64_t key, int
 
 #define GET_NUM_OF_RESULTS(_r) (((_r)->outputBuf) == NULL? 0:((_r)->outputBuf)->info.rows)
 
+//TODO: may need to fine tune this threshold
+#define QUERY_COMP_THRESHOLD (1024 * 512)
+#define NEEDTO_COMPRESS_QUERY(size) ((size) > QUERY_COMP_THRESHOLD ? 1 : 0)
+
 enum {
   // when query starts to execute, this status will set
       QUERY_NOT_COMPLETED = 0x1u,
@@ -638,6 +642,7 @@ int32_t buildArithmeticExprFromMsg(SExprInfo *pArithExprInfo, void *pQueryMsg);
 
 bool isQueryKilled(SQInfo *pQInfo);
 int32_t checkForQueryBuf(size_t numOfTables);
+bool checkNeedToCompressQueryCol(SQInfo *pQInfo);
 bool doBuildResCheck(SQInfo* pQInfo);
 void setQueryStatus(SQueryRuntimeEnv *pRuntimeEnv, int8_t status);
 
@@ -646,7 +651,7 @@ void destroyUdfInfo(SUdfInfo* pUdfInfo);
 
 bool isValidQInfo(void *param);
 
-int32_t doDumpQueryResult(SQInfo *pQInfo, char *data);
+int32_t doDumpQueryResult(SQInfo *pQInfo, char *data, int8_t compressed, int32_t *compLen);
 
 size_t getResultSize(SQInfo *pQInfo, int64_t *numOfRows);
 void setQueryKilled(SQInfo *pQInfo);

src/query/src/qExecutor.c

@@ -4190,26 +4190,60 @@ static void updateNumOfRowsInResultRows(SQueryRuntimeEnv* pRuntimeEnv, SQLFuncti
   }
 }
 
-static void doCopyQueryResultToMsg(SQInfo *pQInfo, int32_t numOfRows, char *data) {
+static int32_t compressQueryColData(SColumnInfoData *pColRes, int32_t numOfRows, char *data, int8_t compressed) {
+  int32_t colSize = pColRes->info.bytes * numOfRows;
+  return (*(tDataTypes[pColRes->info.type].compFunc))(pColRes->pData, colSize, numOfRows, data,
+                                                                 colSize + COMP_OVERFLOW_BYTES, compressed, NULL, 0);
+}
+
+static void doCopyQueryResultToMsg(SQInfo *pQInfo, int32_t numOfRows, char *data, int8_t compressed, int32_t *compLen) {
   SQueryRuntimeEnv* pRuntimeEnv = &pQInfo->runtimeEnv;
   SQueryAttr *pQueryAttr = pRuntimeEnv->pQueryAttr;
 
   SSDataBlock* pRes = pRuntimeEnv->outputBuf;
 
+  int32_t *compSizes = NULL;
+  int32_t numOfCols = pQueryAttr->pExpr2 ? pQueryAttr->numOfExpr2 : pQueryAttr->numOfOutput;
+
+  if (compressed) {
+    compSizes = tcalloc(numOfCols, sizeof(int32_t));
+  }
+
   if (pQueryAttr->pExpr2 == NULL) {
-    for (int32_t col = 0; col < pQueryAttr->numOfOutput; ++col) {
+    for (int32_t col = 0; col < numOfCols; ++col) {
       SColumnInfoData* pColRes = taosArrayGet(pRes->pDataBlock, col);
-      memmove(data, pColRes->pData, pColRes->info.bytes * pRes->info.rows);
+      if (compressed) {
-      data += pColRes->info.bytes * pRes->info.rows;
+        compSizes[col] = compressQueryColData(pColRes, pRes->info.rows, data, compressed);
+        data += compSizes[col];
+        *compLen += compSizes[col];
+        compSizes[col] = htonl(compSizes[col]);
+      } else {
+        memmove(data, pColRes->pData, pColRes->info.bytes * pRes->info.rows);
+        data += pColRes->info.bytes * pRes->info.rows;
+      }
     }
   } else {
-    for (int32_t col = 0; col < pQueryAttr->numOfExpr2; ++col) {
+    for (int32_t col = 0; col < numOfCols; ++col) {
       SColumnInfoData* pColRes = taosArrayGet(pRes->pDataBlock, col);
-      memmove(data, pColRes->pData, pColRes->info.bytes * numOfRows);
+      if (compressed) {
-      data += pColRes->info.bytes * numOfRows;
+        compSizes[col] = htonl(compressQueryColData(pColRes, numOfRows, data, compressed));
+        data += compSizes[col];
+        *compLen += compSizes[col];
+        compSizes[col] = htonl(compSizes[col]);
+      } else {
+        memmove(data, pColRes->pData, pColRes->info.bytes * numOfRows);
+        data += pColRes->info.bytes * numOfRows;
+      }
     }
   }
 
+  if (compressed) {
+    memmove(data, (char *)compSizes, numOfCols * sizeof(int32_t));
+    data += numOfCols * sizeof(int32_t);
+
+    tfree(compSizes);
+  }
+
   int32_t numOfTables = (int32_t) taosHashGetSize(pRuntimeEnv->pTableRetrieveTsMap);
   *(int32_t*)data = htonl(numOfTables);
   data += sizeof(int32_t);
@@ -8692,7 +8726,7 @@ void freeQInfo(SQInfo *pQInfo) {
   tfree(pQInfo);
 }
 
-int32_t doDumpQueryResult(SQInfo *pQInfo, char *data) {
+int32_t doDumpQueryResult(SQInfo *pQInfo, char *data, int8_t compressed, int32_t *compLen) {
   // the remained number of retrieved rows, not the interpolated result
   SQueryRuntimeEnv* pRuntimeEnv = &pQInfo->runtimeEnv;
   SQueryAttr *pQueryAttr = pQInfo->runtimeEnv.pQueryAttr;
@@ -8735,7 +8769,7 @@ int32_t doDumpQueryResult(SQInfo *pQInfo, char *data) {
       setQueryStatus(pRuntimeEnv, QUERY_OVER);
     }
   } else {
-    doCopyQueryResultToMsg(pQInfo, (int32_t)pRuntimeEnv->outputBuf->info.rows, data);
+    doCopyQueryResultToMsg(pQInfo, (int32_t)pRuntimeEnv->outputBuf->info.rows, data, compressed, compLen);
   }
 
   qDebug("QInfo:0x%"PRIx64" current numOfRes rows:%d, total:%" PRId64, pQInfo->qId,
@@ -8821,6 +8855,30 @@ int32_t checkForQueryBuf(size_t numOfTables) {
   return TSDB_CODE_QRY_NOT_ENOUGH_BUFFER;
 }
 
+bool checkNeedToCompressQueryCol(SQInfo *pQInfo) {
+  SQueryRuntimeEnv* pRuntimeEnv = &pQInfo->runtimeEnv;
+  SQueryAttr *pQueryAttr = pRuntimeEnv->pQueryAttr;
+
+  SSDataBlock* pRes = pRuntimeEnv->outputBuf;
+
+  if (GET_NUM_OF_RESULTS(&(pQInfo->runtimeEnv)) <= 0) {
+    return false;
+  }
+
+  int32_t numOfRows = pQueryAttr->pExpr2 ? GET_NUM_OF_RESULTS(pRuntimeEnv) : pRes->info.rows;
+  int32_t numOfCols = pQueryAttr->pExpr2 ? pQueryAttr->numOfExpr2 : pQueryAttr->numOfOutput;
+
+  for (int32_t col = 0; col < numOfCols; ++col) {
+    SColumnInfoData* pColRes = taosArrayGet(pRes->pDataBlock, col);
+    int32_t colSize = pColRes->info.bytes * numOfRows;
+    if (NEEDTO_COMPRESS_QUERY(colSize)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
 void releaseQueryBuf(size_t numOfTables) {
   if (tsQueryBufferSizeBytes < 0) {
     return;

src/query/src/queryMain.c

@@ -324,6 +324,7 @@ int32_t qRetrieveQueryResultInfo(qinfo_t qinfo, bool* buildRes, void* pRspContex
 
 int32_t qDumpRetrieveResult(qinfo_t qinfo, SRetrieveTableRsp **pRsp, int32_t *contLen, bool* continueExec) {
   SQInfo *pQInfo = (SQInfo *)qinfo;
+  int32_t compLen = 0;
 
   if (pQInfo == NULL || !isValidQInfo(pQInfo)) {
     return TSDB_CODE_QRY_INVALID_QHANDLE;
@@ -356,12 +357,21 @@ int32_t qDumpRetrieveResult(qinfo_t qinfo, SRetrieveTableRsp **pRsp, int32_t *co
   }
 
   (*pRsp)->precision = htons(pQueryAttr->precision);
+  (*pRsp)->compressed = (int8_t)(tsCompressColData && checkNeedToCompressQueryCol(pQInfo));
+
   if (GET_NUM_OF_RESULTS(&(pQInfo->runtimeEnv)) > 0 && pQInfo->code == TSDB_CODE_SUCCESS) {
-    doDumpQueryResult(pQInfo, (*pRsp)->data);
+    doDumpQueryResult(pQInfo, (*pRsp)->data, (*pRsp)->compressed, &compLen);
   } else {
     setQueryStatus(pRuntimeEnv, QUERY_OVER);
   }
 
+  if ((*pRsp)->compressed && compLen != 0) {
+    int32_t numOfCols = pQueryAttr->pExpr2 ? pQueryAttr->numOfExpr2 : pQueryAttr->numOfOutput;
+    *contLen = *contLen - pQueryAttr->resultRowSize * s + compLen + numOfCols * sizeof(int32_t);
+    *pRsp = (SRetrieveTableRsp *)rpcReallocCont(*pRsp, *contLen);
+  }
+  (*pRsp)->compLen = htonl(compLen);
+
   pQInfo->rspContext = NULL;
   pQInfo->dataReady  = QUERY_RESULT_NOT_READY;
 

tests/pytest/functions/showOfflineThresholdIs864000.py

@@ -25,7 +25,7 @@ class TDTestCase:
 
     def run(self):
         tdSql.query("show variables")
-        tdSql.checkData(54, 1, 864000)
+        tdSql.checkData(55, 1, 864000)
 
     def stop(self):
         tdSql.close()