New event timers for 8-STABLE

Brandon Gooch jamesbrandongooch at
Fri Nov 12 04:43:53 UTC 2010

2010/11/11 Alexander Motin <mav at>:
> Hi.
> I've created a patch, merging all kernel event timers related stuff from
> HEAD to 8-STABLE. The only thing I have skipped at this moment was mips
> architecture, because of too big code difference there between HEAD and
> 8-STABLE. Patch appeared to be quite large and includes more then 60 SVN
> revisions from HEAD. I hope I haven't missed anything important. I would
> like to ask interested people to test it. Patched code successfully
> builds on all platforms and successfully runs on my amd64 test machine.
> In HEAD code seems to be working enough stable, There only two known
> open issues at the moment:
>  - kernel freeze on XEN HVM when using LAPIC timer in one-shot mode --
> can be workarounded by switching to periodic mode or other timer.
>  - if HPET interrupt shared with other device, system load average may
> lie (report +1 value) -- not a timer problem and not fatal.
> Please report me if you find anything else.
> Latest patch can be found here:
> Merge instructions (list of revisions, if somebody want to redo it):
> After patching you need just rebuild/reinstall the kernel. I haven't
> merged related manual pages yet, so, if needed, consult with man pages
> from HEAD: eventtimers(7), attimer(4), atrtc(4), hpet(4).

Reporting successes! No noticeable anomalies yet, two 8-STABLE systems
(behaving similarly to my 9-CURRENT system in regard to timer
settings). I'll keep prodding away to see what I can break ;) Of
course I'll report the pertinent bits if/when required...

Good job Alexander!


More information about the freebsd-stable mailing list