From 8833a319b9869c75611d218fada7934a3207c1b8 Mon Sep 17 00:00:00 2001
From: xiong_xiaojun <xiong_xiaojun2@huawei.com>
Date: Mon, 24 Aug 2020 17:34:59 +0800
Subject: [PATCH] fix csnlog cannot be found thar occur in standby node, and
 remove the Warning log in InternalGetCommitSeqNo.

---
 .../storage/access/transam/csnlog.cpp         | 21 -------------------
 .../storage/access/transam/xlog.cpp           |  8 ++++++-
 src/gausskernel/storage/ipc/procarray.cpp     |  2 --
 3 files changed, 7 insertions(+), 24 deletions(-)

diff --git a/src/gausskernel/storage/access/transam/csnlog.cpp b/src/gausskernel/storage/access/transam/csnlog.cpp
index e35ff949d..b23cb1b5b 100755
--- a/src/gausskernel/storage/access/transam/csnlog.cpp
+++ b/src/gausskernel/storage/access/transam/csnlog.cpp
@@ -413,27 +413,6 @@ static CommitSeqNo InternalGetCommitSeqNo(TransactionId xid)
     int slotno;
     CommitSeqNo csn;
 
-    /* Can't ask about stuff that might not be around anymore */
-    TransactionId currGlobalXmin = pg_atomic_read_u64(&t_thrd.xact_cxt.ShmemVariableCache->recentGlobalXmin);
-
-#ifdef ENABLE_MULTIPLE_NODES
-    if (TransactionIdPrecedes(xid, currGlobalXmin))
-#else
-    if (TransactionIdPrecedes(xid, currGlobalXmin) && !RecoveryInProgress())
-#endif
-    {
-        ereport(WARNING,
-            (errcode(ERRCODE_SNAPSHOT_INVALID),
-                (errmsg("Snapshot too old when read CSN, this is a safe error"
-                        "if there is breakdown in gtm of CN log"),
-                    errdetail("current xid %lu is lower than "
-                              "recentGlobalXmin: %lu",
-                        xid,
-                        currGlobalXmin),
-                    errhint("This is a safe error report, will not impact "
-                            "data consistency, retry your query if needed."))));
-    }
-
     if (!TransactionIdIsNormal(xid)) {
         if (xid == InvalidTransactionId)
             return COMMITSEQNO_ABORTED;
diff --git a/src/gausskernel/storage/access/transam/xlog.cpp b/src/gausskernel/storage/access/transam/xlog.cpp
index 10ca376be..056349da4 100755
--- a/src/gausskernel/storage/access/transam/xlog.cpp
+++ b/src/gausskernel/storage/access/transam/xlog.cpp
@@ -10891,7 +10891,13 @@ bool CreateRestartPoint(int flags)
          */
         if (!g_instance.attr.attr_storage.enableIncrementalCheckpoint ||
             elapsed_secs >= u_sess->attr.attr_storage.fullCheckPointTimeout) {
-            TruncateCSNLOG(GetOldestXmin(NULL));
+            TransactionId globalXmin = InvalidTransactionId;
+            (void)GetOldestActiveTransactionId(&globalXmin);
+            TransactionId cutoff_xid = GetOldestXmin(NULL);
+            if (TransactionIdIsNormal(globalXmin) && TransactionIdPrecedes(globalXmin, cutoff_xid)) {
+                cutoff_xid = globalXmin;
+            }
+            TruncateCSNLOG(cutoff_xid);
             t_thrd.checkpoint_cxt.last_truncate_log_time = now;
         }
     }
diff --git a/src/gausskernel/storage/ipc/procarray.cpp b/src/gausskernel/storage/ipc/procarray.cpp
index a9782d710..0877e6a19 100644
--- a/src/gausskernel/storage/ipc/procarray.cpp
+++ b/src/gausskernel/storage/ipc/procarray.cpp
@@ -2050,8 +2050,6 @@ TransactionId GetOldestActiveTransactionId(TransactionId *globalXmin)
     TransactionIdAdvance(xmax);
     TransactionId xmin = xmax;
 
-    Assert(!RecoveryInProgress());
-
     LWLockAcquire(ProcArrayLock, LW_SHARED);
 
     /*