Don't forget to flush XLOG_PARAMETER_CHANGE record.

MasaoFujii · MasaoFujii · commit 6fe8411ffb71 · 2014-03-26T02:14:01.000+09:00
Backpatch to 9.0 where XLOG_PARAMETER_CHANGE record was instroduced.
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
@@ -8803,6 +8803,7 @@ XLogReportParameters(void)
 		{
 			XLogRecData rdata;
 			xl_parameter_change xlrec;
+			XLogRecPtr	recptr;
 
 			xlrec.MaxConnections = MaxConnections;
 			xlrec.max_prepared_xacts = max_prepared_xacts;
@@ -8814,7 +8815,8 @@ XLogReportParameters(void)
 			rdata.len = sizeof(xlrec);
 			rdata.next = NULL;
 
-			XLogInsert(RM_XLOG_ID, XLOG_PARAMETER_CHANGE, &rdata);
+			recptr = XLogInsert(RM_XLOG_ID, XLOG_PARAMETER_CHANGE, &rdata);
+			XLogFlush(recptr);
 		}
 
 		ControlFile->MaxConnections = MaxConnections;

Original file line number	Diff line number	Diff line change
`@@ -8803,6 +8803,7 @@ XLogReportParameters(void)`
`8803`	`8803`	`{`
`8804`	`8804`	`XLogRecData rdata;`
`8805`	`8805`	`xl_parameter_change xlrec;`
	`8806`	`+ XLogRecPtr recptr;`
`8806`	`8807`
`8807`	`8808`	`xlrec.MaxConnections = MaxConnections;`
`8808`	`8809`	`xlrec.max_prepared_xacts = max_prepared_xacts;`
`@@ -8814,7 +8815,8 @@ XLogReportParameters(void)`
`8814`	`8815`	`rdata.len = sizeof(xlrec);`
`8815`	`8816`	`rdata.next = NULL;`
`8816`	`8817`
`8817`		`- XLogInsert(RM_XLOG_ID, XLOG_PARAMETER_CHANGE, &rdata);`
	`8818`	`+ recptr = XLogInsert(RM_XLOG_ID, XLOG_PARAMETER_CHANGE, &rdata);`
	`8819`	`+ XLogFlush(recptr);`
`8818`	`8820`	`}`
`8819`	`8821`
`8820`	`8822`	`ControlFile->MaxConnections = MaxConnections;`