Spike of transaction deadlocks appeared on dewiki today, involving dozens of these two query types fighting for locks:
DELETE /* RecentChangesUpdateJob::purgeExpiredRows (jobrunner client IPs) INSERT /* RecentChange::save (all with bot user names, various MW client IPs)
Merlissimo noticed it:
[00:24:52] <Merlissimo> rc table for dewiki is missing updates for about twenty minutes. is this problem already known? [00:25:45] <Krenair> in labs? [00:25:53] <Merlissimo> in specialpages [00:26:03] <Merlissimo> and in labs, too [00:26:55] <TimStarling> https://de.wikipedia.org/wiki/Spezial:Letzte_%C3%84nderungen looks correct to me [00:28:07] <Merlissimo> between 21:47 and 22:05 [00:28:40] <Merlissimo> e.g. no new pages on https://de.wikipedia.org/wiki/Spezial:Neue_Seiten in this time [00:28:58] <Merlissimo> 23:47-00:05 in german time [00:29:47] <Merlissimo> e.g. https://de.wikipedia.org/wiki/Werbowe_%28Polohy%29 is missing there [00:50:08] <TimStarling> Merlissimo: we're looking at it
Need to:
- Resolve this particular gap
- Reduce the potential for such clashes