From f5d45bdf683dbba0ff910abeabd9b9466181c36d Mon Sep 17 00:00:00 2001
From: openGaussDev <zhangchengzhe@huawei.com>
Date: Tue, 6 Aug 2024 14:45:33 +0800
Subject: [PATCH] =?UTF-8?q?=20=E4=BF=AE=E5=A4=8D=E5=A4=87=E6=9C=BA?=
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Match-id-06894f7e495d72c5763653105cbd2c8eee989c81
---
 src/gausskernel/storage/buffer/bufmgr.cpp | 23 +++++++++++++++++++++++
 src/gausskernel/storage/ipc/procarray.cpp |  4 +++-
 src/include/storage/buf/bufmgr.h          |  1 +
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/src/gausskernel/storage/buffer/bufmgr.cpp b/src/gausskernel/storage/buffer/bufmgr.cpp
index e062afafd..d5d15f30b 100644
--- a/src/gausskernel/storage/buffer/bufmgr.cpp
+++ b/src/gausskernel/storage/buffer/bufmgr.cpp
@@ -4764,6 +4764,29 @@ int GetThreadBufferLeakNum(void)
     return refCountErrors;
 }
 
+bool CheckForBufferPin(void)
+{
+    PrivateRefCountEntry *res = NULL;
+
+    for (int i = 0; i < REFCOUNT_ARRAY_ENTRIES; i++) {
+        res = &t_thrd.storage_cxt.PrivateRefCountArray[i];
+
+        if (res->buffer != InvalidBuffer) {
+            return true;
+        }
+    }
+
+    if (t_thrd.storage_cxt.PrivateRefCountOverflowed) {
+        HASH_SEQ_STATUS hstat;
+        hash_seq_init(&hstat, t_thrd.storage_cxt.PrivateRefCountHash);
+        while ((res = (PrivateRefCountEntry *)hash_seq_search(&hstat)) != NULL) {
+            hash_seq_term(&hstat);
+            return true;
+        }
+    }
+    return false;
+}
+
 /*
  *		CheckForBufferLeaks - ensure this backend holds no buffer pins
  *
diff --git a/src/gausskernel/storage/ipc/procarray.cpp b/src/gausskernel/storage/ipc/procarray.cpp
index d55df5110..4f012ce0a 100755
--- a/src/gausskernel/storage/ipc/procarray.cpp
+++ b/src/gausskernel/storage/ipc/procarray.cpp
@@ -2120,6 +2120,8 @@ RETRY:
     bool retry_get = false;
     uint64 retry_count = 0;
     const static uint64 WAIT_COUNT = 0x7FFFF;
+    bool get_snapshot_by_self = CheckForBufferPin() || forHSFeedBack;
+
     /* reset xmin before acquiring lwlock, in case blocking redo */
     t_thrd.pgxact->xmin = InvalidTransactionId;
 RETRY_GET:
@@ -2184,7 +2186,7 @@ RETRY_GET:
                 goto RETRY_GET;
             }
 #ifndef ENABLE_MULTIPLE_NODES
-        } else if (forHSFeedBack) {
+        } else if (get_snapshot_by_self) {
             LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
             if ((t_thrd.xact_cxt.ShmemVariableCache->standbyXmin
                 <= t_thrd.xact_cxt.ShmemVariableCache->standbyRedoCleanupXmin)
diff --git a/src/include/storage/buf/bufmgr.h b/src/include/storage/buf/bufmgr.h
index 63a8f9bce..2c0f6da63 100644
--- a/src/include/storage/buf/bufmgr.h
+++ b/src/include/storage/buf/bufmgr.h
@@ -410,6 +410,7 @@ extern void RangeForgetBuffer(RelFileNode node, ForkNumber forkNum, BlockNumber
 
 extern void DropSegRelNodeSharedBuffer(RelFileNode node, ForkNumber forkNum);
 extern int GetThreadBufferLeakNum(void);
+extern bool CheckForBufferPin(void);
 extern void flush_all_buffers(Relation rel, Oid db_id, HTAB *hashtbl = NULL);
 /* in localbuf.c */
 extern void ForgetLocalBuffer(RelFileNode rnode, ForkNumber forkNum, BlockNumber blockNum);