diff --git a/src/common/inc/tglobal.h b/src/common/inc/tglobal.h
index 515115c323294a67318b5eb1dd17660e651d09f8..4636eaac08db4943e1837b5d6e8db40341ba6546 100644
--- a/src/common/inc/tglobal.h
+++ b/src/common/inc/tglobal.h
@@ -44,14 +44,17 @@ extern int32_t  tsMaxShellConns;
 extern int32_t  tsShellActivityTimer;
 extern uint32_t tsMaxTmrCtrl;
 extern float    tsNumOfThreadsPerCore;
-extern float    tsRatioOfQueryThreads;
+extern float    tsRatioOfQueryThreads;  // todo remove it
 extern int8_t   tsDaylight;
 extern char     tsTimezone[];
 extern char     tsLocale[];
-extern char     tsCharset[];  // default encode string
+extern char     tsCharset[];            // default encode string
 extern int32_t  tsEnableCoreFile;
 extern int32_t  tsCompressMsgSize;
 
+//query buffer management
+extern int32_t  tsQueryBufferSize;      // maximum allowed usage buffer for each data node during query processing
+
 // client
 extern int32_t tsTableMetaKeepTimer;
 extern int32_t tsMaxSQLStringLen;
diff --git a/src/common/src/tglobal.c b/src/common/src/tglobal.c
index c24ba490ba7f4cb25ba032b0404790d68540c826..09ccdacc94f2877b5fcb974094453a7c8639f5c5 100644
--- a/src/common/src/tglobal.c
+++ b/src/common/src/tglobal.c
@@ -45,14 +45,14 @@ int32_t  tsEnableTelemetryReporting = 1;
 char     tsEmail[TSDB_FQDN_LEN] = {0};
 
 // common
-int32_t tsRpcTimer = 1000;
-int32_t tsRpcMaxTime = 600;  // seconds;
-int32_t tsMaxShellConns = 5000;
+int32_t tsRpcTimer       = 1000;
+int32_t tsRpcMaxTime     = 600;  // seconds;
+int32_t tsMaxShellConns  = 5000;
 int32_t tsMaxConnections = 5000;
-int32_t tsShellActivityTimer = 3;  // second
-float   tsNumOfThreadsPerCore = 1.0;
-float   tsRatioOfQueryThreads = 0.5;
-int8_t  tsDaylight = 0;
+int32_t tsShellActivityTimer  = 3;  // second
+float   tsNumOfThreadsPerCore = 1.0f;
+float   tsRatioOfQueryThreads = 0.5f;
+int8_t  tsDaylight       = 0;
 char    tsTimezone[TSDB_TIMEZONE_LEN] = {0};
 char    tsLocale[TSDB_LOCALE_LEN] = {0};
 char    tsCharset[TSDB_LOCALE_LEN] = {0};  // default encode string
@@ -99,6 +99,12 @@ float tsStreamComputDelayRatio = 0.1f;
 int32_t tsProjectExecInterval = 10000;   // every 10sec, the projection will be executed once
 int64_t tsMaxRetentWindow = 24 * 3600L;  // maximum time window tolerance
 
+// the maximum allowed query buffer size during query processing for each data node.
+// -1 no limit (default)
+// 0  no query allowed, queries are disabled
+// positive value (in MB)
+int32_t tsQueryBufferSize = -1;
+
 // db parameters
 int32_t tsCacheBlockSize = TSDB_DEFAULT_CACHE_BLOCK_SIZE;
 int32_t tsBlocksPerVnode = TSDB_DEFAULT_TOTAL_BLOCKS;
@@ -676,7 +682,7 @@ static void doInitGlobalConfig(void) {
   cfg.minValue = TSDB_MIN_CACHE_BLOCK_SIZE;
   cfg.maxValue = TSDB_MAX_CACHE_BLOCK_SIZE;
   cfg.ptrLength = 0;
-  cfg.unitType = TAOS_CFG_UTYPE_Mb;
+  cfg.unitType = TAOS_CFG_UTYPE_MB;
   taosInitConfigOption(cfg);
 
   cfg.option = "blocks";
@@ -839,6 +845,16 @@ static void doInitGlobalConfig(void) {
   cfg.unitType = TAOS_CFG_UTYPE_NONE;
   taosInitConfigOption(cfg);
 
+  cfg.option = "queryBufferSize";
+  cfg.ptr = &tsQueryBufferSize;
+  cfg.valType = TAOS_CFG_VTYPE_INT32;
+  cfg.cfgType = TSDB_CFG_CTYPE_B_CONFIG | TSDB_CFG_CTYPE_B_SHOW;
+  cfg.minValue = -1;
+  cfg.maxValue = 10000000000000;  //10TB
+  cfg.ptrLength = 0;
+  cfg.unitType = TAOS_CFG_UTYPE_BYTE;
+  taosInitConfigOption(cfg);
+
   // locale & charset
   cfg.option = "timezone";
   cfg.ptr = tsTimezone;
diff --git a/src/inc/query.h b/src/inc/query.h
index 0c18f85dc31bae5e77bae7228d5390a8d32df07a..5e1de77889cc469566cc94b729c55622e5462bd6 100644
--- a/src/inc/query.h
+++ b/src/inc/query.h
@@ -78,7 +78,6 @@ int32_t qKillQuery(qinfo_t qinfo);
 
 int32_t qQueryCompleted(qinfo_t qinfo);
 
-
 /**
  * destroy query info structure
  * @param qHandle
diff --git a/src/inc/taoserror.h b/src/inc/taoserror.h
index bb111d2da0da75e6a3e3812ac21364f9a18fb6f3..e64b7974507a7cf9c9606639dfbf4f42a4b44bc1 100644
--- a/src/inc/taoserror.h
+++ b/src/inc/taoserror.h
@@ -230,6 +230,7 @@ TAOS_DEFINE_ERROR(TSDB_CODE_QRY_NOT_READY,                0, 0x0707, "Query not
 TAOS_DEFINE_ERROR(TSDB_CODE_QRY_HAS_RSP,                  0, 0x0708, "Query should response")
 TAOS_DEFINE_ERROR(TSDB_CODE_QRY_IN_EXEC,                  0, 0x0709, "Multiple retrieval of this query")
 TAOS_DEFINE_ERROR(TSDB_CODE_QRY_TOO_MANY_TIMEWINDOW,      0, 0x070A, "Too many time window in query")
+TAOS_DEFINE_ERROR(TSDB_CODE_QRY_NOT_ENOUGH_BUFFER,      0, 0x070B, "Query buffer limit has reached")
 
 // grant
 TAOS_DEFINE_ERROR(TSDB_CODE_GRANT_EXPIRED,                0, 0x0800, "License expired")
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 37394b9769104b9d5e3c48edc96ddb5391bede9d..0ed47ff66ab9a600825dcc75072023254a0ad75a 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -194,6 +194,8 @@ static void buildTagQueryResult(SQInfo *pQInfo);
 
 static int32_t setAdditionalInfo(SQInfo *pQInfo, void *pTable, STableQueryInfo *pTableQueryInfo);
 static int32_t flushFromResultBuf(SQueryRuntimeEnv* pRuntimeEnv, SGroupResInfo* pGroupResInfo);
+static int32_t checkForQueryBuf(int32_t numOfTables);
+static void releaseQueryBuf(int32_t numOfTables);
 
 bool doFilterData(SQuery *pQuery, int32_t elemPos) {
   for (int32_t k = 0; k < pQuery->numOfFilterCols; ++k) {
@@ -6492,6 +6494,8 @@ static void freeQInfo(SQInfo *pQInfo) {
 
   qDebug("QInfo:%p start to free QInfo", pQInfo);
 
+  releaseQueryBuf(pQInfo->tableqinfoGroupInfo.numOfTables);
+
   teardownQueryRuntimeEnv(&pQInfo->runtimeEnv);
 
   SQuery *pQuery = pQInfo->runtimeEnv.pQuery;
@@ -6726,6 +6730,11 @@ int32_t qCreateQueryInfo(void* tsdb, int32_t vgId, SQueryTableMsg* pQueryMsg, qi
     assert(0);
   }
 
+  code = checkForQueryBuf(tableGroupInfo.numOfTables);
+  if (code != TSDB_CODE_SUCCESS) {  // not enough query buffer, abort
+    goto _over;
+  }
+
   (*pQInfo) = createQInfoImpl(pQueryMsg, pGroupbyExpr, pExprs, &tableGroupInfo, pTagColumnInfo, isSTableQuery);
   pExprs = NULL;
   pGroupbyExpr = NULL;
@@ -7127,6 +7136,48 @@ static void buildTagQueryResult(SQInfo* pQInfo) {
   setQueryStatus(pQuery, QUERY_COMPLETED);
 }
 
+static int64_t getQuerySupportBufSize(int32_t numOfTables) {
+  size_t s1 = sizeof(STableQueryInfo);
+  size_t s2 = sizeof(SHashNode);
+
+//  size_t s3 = sizeof(STableCheckInfo);  buffer consumption in tsdb
+  return (s1 + s2) * 1.5 * numOfTables;
+}
+
+int32_t checkForQueryBuf(int32_t numOfTables) {
+  int64_t t = getQuerySupportBufSize(numOfTables);
+  if (tsQueryBufferSize < 0) {
+    return true;
+  } else if (tsQueryBufferSize > 0) {
+
+    while(1) {
+      int64_t s = tsQueryBufferSize;
+      int64_t remain = s - t;
+      if (remain >= 0) {
+        if (atomic_val_compare_exchange_64(&tsQueryBufferSize, s, remain) == s) {
+          return TSDB_CODE_SUCCESS;
+        }
+      } else {
+        return TSDB_CODE_QRY_NOT_ENOUGH_BUFFER;
+      }
+    }
+  }
+
+  // disable query processing if the value of tsQueryBufferSize is zero.
+  return TSDB_CODE_QRY_NOT_ENOUGH_BUFFER;
+}
+
+void releaseQueryBuf(int32_t numOfTables) {
+  if (tsQueryBufferSize <= 0) {
+    return;
+  }
+
+  int64_t t = getQuerySupportBufSize(numOfTables);
+
+  // restore value is not enough buffer available
+  atomic_add_fetch_64(&tsQueryBufferSize, t);
+}
+
 void* qGetResultRetrieveMsg(qinfo_t qinfo) {
   SQInfo* pQInfo = (SQInfo*) qinfo;
   assert(pQInfo != NULL);
diff --git a/src/util/inc/tconfig.h b/src/util/inc/tconfig.h
index 0520cf29a87c9d4727ef6db48d8f5712ac845b89..33819f6a20ee64ada194d520ef09c6133d4dad96 100644
--- a/src/util/inc/tconfig.h
+++ b/src/util/inc/tconfig.h
@@ -53,7 +53,7 @@ enum {
   TAOS_CFG_UTYPE_NONE,
   TAOS_CFG_UTYPE_PERCENT,
   TAOS_CFG_UTYPE_GB,
-  TAOS_CFG_UTYPE_Mb,
+  TAOS_CFG_UTYPE_MB,
   TAOS_CFG_UTYPE_BYTE,
   TAOS_CFG_UTYPE_SECOND,
   TAOS_CFG_UTYPE_MS