diff --git a/src/gausskernel/process/stream/streamCore.cpp b/src/gausskernel/process/stream/streamCore.cpp
index 25fbd65d3..e39dcebe4 100755
--- a/src/gausskernel/process/stream/streamCore.cpp
+++ b/src/gausskernel/process/stream/streamCore.cpp
@@ -74,6 +74,7 @@ MemoryContext StreamNodeGroup::m_memoryGlobalCxt = NULL;
 pthread_mutex_t StreamNodeGroup::m_streamNodeGroupLock;
 HTAB* StreamNodeGroup::m_streamNodeGroupTbl = NULL;
 HTAB* StreamNodeGroup::m_streamConnectSyncTbl = NULL;
+HTAB* StreamNodeGroup::m_streamDescHashTbl = NULL;
 pthread_mutex_t StreamNodeGroup::m_streamConnectSyncLock;
 
 static void ConsumerNodeSyncUpMessage(RecursiveUnionController* controller, int step, StreamState* node);
@@ -439,6 +440,15 @@ void StreamNodeGroup::StartUp()
         hash_create("stream connect sync hash", 256, &nodectl, HASH_ELEM | HASH_FUNCTION | HASH_SHRCTX);
 
     pthread_mutex_init(&m_streamConnectSyncLock, NULL);
+    rc = memset_s(&nodectl, sizeof(nodectl), 0, sizeof(nodectl));
+    securec_check(rc, "\0", "\0");
+    nodectl.keysize = sizeof(StreamKey);
+    nodectl.entrysize = sizeof(StreamDescElement);
+    nodectl.hash = tag_hash;
+    nodectl.hcxt = m_memoryGlobalCxt;
+
+    m_streamDescHashTbl =
+        hash_create("stream desc hash", STREAM_DESC_HASH_NUMBER, &nodectl, HASH_ELEM | HASH_FUNCTION | HASH_SHRCTX);
 }
 
 /*
@@ -1908,6 +1918,7 @@ void StreamNodeGroup::MarkRecursiveVfdInvalid()
 void StreamNodeGroup::BuildStreamDesc(const uint64& queryId, Plan* node)
 {
     StreamKey streamKey;
+    memset_s(&streamKey, sizeof(streamKey), 0, sizeof(streamKey));
     streamKey.queryId = queryId;
     streamKey.planNodeId = node->plan_node_id;
 
@@ -1927,31 +1938,34 @@ void StreamNodeGroup::BuildStreamDesc(const uint64& queryId, Plan* node)
     if (!parallelDesc) {
         return;
     }
-
-    m_streamDesc.insert({streamKey, parallelDesc});
+    bool found = false;
+    StreamDescElement* element = (StreamDescElement*)hash_search(m_streamDescHashTbl, &streamKey, HASH_ENTER, &found);
+    if (found != false) {
+        ereport(ERROR, (errcode(ERRCODE_SYSTEM_ERROR), errmsg("streamKey of stream nodegroup id is duplicated")));
+    }
+    element->key = streamKey;
+    element->parallelDesc = (ParallelIndexScanDescData*)parallelDesc;
 }
 
 void StreamNodeGroup::DestroyStreamDesc(const uint64& queryId, Plan* node)
 {
     StreamKey streamKey;
+    memset_s(&streamKey, sizeof(streamKey), 0, sizeof(streamKey));
     streamKey.queryId = queryId;
     streamKey.planNodeId = node->plan_node_id;
-
-    std::unordered_map<StreamKey, void*, KeyHash, KeyEqual>::iterator iter;
+    bool found = false;
+    StreamDescElement* element = NULL;
 
     switch (nodeTag(node)) {
         case T_IndexScan:
-            iter = m_streamDesc.find(streamKey);
-            if (m_streamDesc.end() == iter) {
-                return;
-            }
-            if (iter->second) {
-                if (((ParallelIndexScanDescData*)iter->second)->psBtpscan) {
-                    delete ((ParallelIndexScanDescData*)iter->second)->psBtpscan;
+            element = (StreamDescElement*)hash_search(m_streamDescHashTbl, &streamKey, HASH_FIND, &found);
+            if (found == true) {
+                if (((ParallelIndexScanDescData*)element->parallelDesc)->psBtpscan) {
+                    delete ((ParallelIndexScanDescData*)element->parallelDesc)->psBtpscan;
                 }
-                pfree(iter->second);
+                pfree(element->parallelDesc);
+                (StreamDescElement*)hash_search(m_streamDescHashTbl, &streamKey, HASH_REMOVE, NULL);
             }
-            m_streamDesc.erase(streamKey);
             break;
         default:
             break;
@@ -1961,10 +1975,16 @@ void StreamNodeGroup::DestroyStreamDesc(const uint64& queryId, Plan* node)
 void* StreamNodeGroup::GetParalleDesc(const uint64& queryId, const uint64& planNodeId)
 {
     StreamKey key;
+    memset_s(&key, sizeof(key), 0, sizeof(key));
     key.queryId = queryId;
     key.planNodeId = planNodeId;
-    std::unordered_map<StreamKey, void*, KeyHash, KeyEqual>::iterator iter = m_streamDesc.find(key);
-    return (m_streamDesc.end() == iter) ? NULL : iter->second;
+    bool found = false;
+    StreamDescElement* element = (StreamDescElement*)hash_search(m_streamDescHashTbl, &key, HASH_FIND, &found);
+    if (found == false) {
+        return NULL;
+    } else {
+        return element->parallelDesc;
+    }
 }
 
 #ifndef ENABLE_MULTIPLE_NODES
diff --git a/src/include/distributelayer/streamCore.h b/src/include/distributelayer/streamCore.h
index b4dacb7e4..d7f191780 100755
--- a/src/include/distributelayer/streamCore.h
+++ b/src/include/distributelayer/streamCore.h
@@ -28,7 +28,6 @@
 #define SRC_INCLUDE_DISTRIBUTELAYER_STREAMCORE_H_
 
 #include <signal.h>
-#include <unordered_map>
 
 #include "postgres.h"
 #include "knl/knl_variable.h"
@@ -59,6 +58,8 @@
 
 #define TupleVectorMaxSize 100
 
+#define STREAM_DESC_HASH_NUMBER 256
+
 #define IS_STREAM_PORTAL (!StreamThreadAmI() && portal->streamInfo.streamGroup != NULL)
 
 struct StreamState;
@@ -104,6 +105,11 @@ typedef struct {
     uint64 key;
 } StreamConnectSyncElement;
 
+typedef struct {
+    StreamKey key;
+    ParallelIndexScanDescData* parallelDesc;
+} StreamDescElement;
+
 enum StreamObjType {
     STREAM_PRODUCER,
     STREAM_CONSUMER,
@@ -526,21 +532,7 @@ private:
     /* Mark Stream query quit status. */
     StreamObjStatus m_quitStatus;
 #endif
-    struct KeyHash {
-        std::size_t operator()(const StreamKey& k) const
-        {
-            return std::hash<uint>()(k.queryId) ^
-                    (std::hash<uint>()(k.planNodeId) << 1);
-        }
-    };
-
-    struct KeyEqual {
-        bool operator()(const StreamKey& lhs, const StreamKey& rhs) const
-        {
-            return lhs.queryId == rhs.queryId && lhs.planNodeId == rhs.planNodeId;
-        }
-    };
-    std::unordered_map<StreamKey, void*, KeyHash, KeyEqual> m_streamDesc;
+    static HTAB* m_streamDescHashTbl;
 };
 
 extern bool IsThreadProcessStreamRecursive();
diff --git a/src/include/executor/node/nodeBitmapHeapscan.h b/src/include/executor/node/nodeBitmapHeapscan.h
index 9f6560123..0b0f1a411 100644
--- a/src/include/executor/node/nodeBitmapHeapscan.h
+++ b/src/include/executor/node/nodeBitmapHeapscan.h
@@ -29,6 +29,4 @@ extern int TableScanBitmapNextTargetRel(TableScanDesc scan, BitmapHeapScanState
 extern TupleTableSlot* ExecBitmapHeapScan(PlanState* state);
 extern void ExecInitPartitionForBitmapHeapScan(BitmapHeapScanState* scanstate, EState* estate);
 
-#define BITMAP_PREFETCH_PAGE_RATIO 2
-
 #endif /* NODEBITMAPHEAPSCAN_H */