From: Willy Tarreau <w@1wt.eu>
Date: Wed, 3 Sep 2025 09:54:15 +0000 (+0200)
Subject: OPTIM: stick-tables: exit expiry faster when the update lock is held
X-Git-Tag: v3.3-dev8~26
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=46463d68502345976fd76fcd1d190cfe4ecb083c;p=thirdparty%2Fhaproxy.git

OPTIM: stick-tables: exit expiry faster when the update lock is held

It helps keep the contention level low: when we hold the update lock
that we know other parts may be relying on (peers, track-sc etc),
we decrease the remaining visit counters 4 times as fast to further
reduce the contention. At this point no more warnings are seen during
intense synchronization (2x64 cores, 1.5M req/s with a track-sc each,
5M entries in use).
---

diff --git a/src/stick_table.c b/src/stick_table.c
index e6dbe99a4..a73b30a95 100644
--- a/src/stick_table.c
+++ b/src/stick_table.c
@@ -936,7 +936,8 @@ struct task *process_table_expire(struct task *task, void *context, unsigned int
 				goto out_unlock;
 			}
 
-			to_visit--;
+			/* Let's quit earlier if we currently hold the update lock */
+			to_visit -= 1 + 3 * updt_locked;
 
 			/* timer looks expired, detach it from the queue */
 			ts = eb32_entry(eb, struct stksess, exp);