postgres.git / summary / log / commit / refs

commit    8de3b68faffcb5898244bd8af3abfb6edb11543f
Author:   Alvaro Herrera <alvherre@alvh.no-ip.org>
Date:     Tue Jan 07 20:38:48 2020 +0000
First released in: 13.0, 10.12, 11.7, 12.2

    pg_stat_activity: show NULL stmt start time for walsenders
    
    Returning a non-NULL time is pointless, sinc a walsender is not a
    process that would be running normal transactions anyway, but the code
    was unintentionally exposing the process start time intermittently,
    which was not only bogus but it also confused monitoring systems looking
    for idle transactions.  Fix by avoiding all updates in walsenders.
    
    Backpatch to pg10: previously I misidentified the branches that show
    auxiliary processes in pg_stat_activity.
    
    Reported-by: Tomas Vondra
    Discussion: https://postgr.es/m/20191209234409.exe7osmyalwkt5j4@development


 src/backend/access/transam/xact.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 9b252213d95..0dd6b82f99a 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -758,6 +758,13 @@ GetCurrentTransactionStopTimestamp(void)
 void
 SetCurrentStatementStartTimestamp(void)
 {
+	/*
+	 * Skip if on a walsender; this is not needed, and it confuses monitoring
+	 * if we publish non-NULL values.
+	 */
+	if (am_walsender)
+		return;
+
 	if (!IsParallelWorker())
 		stmtStartTimestamp = GetCurrentTimestamp();
 	else


[parent: 66fd0adc73a8]