[Bug 264867] kevent EVFILT_TIMER, timer expiration with twice the period
Date: Thu, 30 Jun 2022 18:26:47 UTC
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=264867 --- Comment #8 from Mark Johnston <markj@FreeBSD.org> --- Created attachment 235005 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=235005&action=edit possible bug fix Could you please give this patch a try? It solves the problem for me. I think testing this would be more useful than the other things I suggested so far (pinning threads, etc.). I think it'll apply to 13.1 and 12.3 without any adjustment. Basically, when scheduling a callout on a different CPU, there is a small race which can cause the event timer to be programmed incorrectly, resulting in delayed processing of events. Your excellent test program triggers this readily on one of my systems with many CPUs; over time the scheduler migrates threads away from the "home" CPU selected during knote initialization, so the window for this race is opened. -- You are receiving this mail because: You are the assignee for the bug.