From: Nathan Bossart <nathan@postgresql.org>
Date: Sat, 12 Jul 2025 19:34:57 +0000 (-0500)
Subject: Remove XLogCtl->ckptFullXid.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;ds=inline;p=thirdparty%2Fpostgresql.git

Remove XLogCtl->ckptFullXid.

A few code paths set this variable, but its value is never used.

Oversight in commit 2fc7af5e96.

Reviewed-by: Aleksander Alekseev <aleksander@tigerdata.com>
Discussion: https://postgr.es/m/aHFyE1bs9YR93dQ1%40nathan
---

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 88fb9b45b2a..8e7827c6ed9 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -449,7 +449,6 @@ typedef struct XLogCtlData
 	/* Protected by info_lck: */
 	XLogwrtRqst LogwrtRqst;
 	XLogRecPtr	RedoRecPtr;		/* a recent copy of Insert->RedoRecPtr */
-	FullTransactionId ckptFullXid;	/* nextXid of latest checkpoint */
 	XLogRecPtr	asyncXactLSN;	/* LSN of newest async commit/abort */
 	XLogRecPtr	replicationSlotMinLSN;	/* oldest LSN needed by any slot */
 
@@ -5744,7 +5743,6 @@ StartupXLOG(void)
 	SetMultiXactIdLimit(checkPoint.oldestMulti, checkPoint.oldestMultiDB, true);
 	SetCommitTsLimit(checkPoint.oldestCommitTsXid,
 					 checkPoint.newestCommitTsXid);
-	XLogCtl->ckptFullXid = checkPoint.nextXid;
 
 	/*
 	 * Clear out any old relcache cache files.  This is *necessary* if we do
@@ -7437,11 +7435,6 @@ CreateCheckPoint(int flags)
 	UpdateControlFile();
 	LWLockRelease(ControlFileLock);
 
-	/* Update shared-memory copy of checkpoint XID/epoch */
-	SpinLockAcquire(&XLogCtl->info_lck);
-	XLogCtl->ckptFullXid = checkPoint.nextXid;
-	SpinLockRelease(&XLogCtl->info_lck);
-
 	/*
 	 * We are now done with critical updates; no need for system panic if we
 	 * have trouble while fooling with old log segments.
@@ -8516,11 +8509,6 @@ xlog_redo(XLogReaderState *record)
 		ControlFile->checkPointCopy.nextXid = checkPoint.nextXid;
 		LWLockRelease(ControlFileLock);
 
-		/* Update shared-memory copy of checkpoint XID/epoch */
-		SpinLockAcquire(&XLogCtl->info_lck);
-		XLogCtl->ckptFullXid = checkPoint.nextXid;
-		SpinLockRelease(&XLogCtl->info_lck);
-
 		/*
 		 * We should've already switched to the new TLI before replaying this
 		 * record.
@@ -8577,11 +8565,6 @@ xlog_redo(XLogReaderState *record)
 		ControlFile->checkPointCopy.nextXid = checkPoint.nextXid;
 		LWLockRelease(ControlFileLock);
 
-		/* Update shared-memory copy of checkpoint XID/epoch */
-		SpinLockAcquire(&XLogCtl->info_lck);
-		XLogCtl->ckptFullXid = checkPoint.nextXid;
-		SpinLockRelease(&XLogCtl->info_lck);
-
 		/* TLI should not change in an on-line checkpoint */
 		(void) GetCurrentReplayRecPtr(&replayTLI);
 		if (checkPoint.ThisTimeLineID != replayTLI)