On Wed, Mar 03, 2010 at 11:16:51AM +0000, Tom Evans wrote: > On Wed, Mar 3, 2010 at 11:09 AM, Jeremy Chadwick > <free...@jdc.parodius.com> wrote: > > On Wed, Mar 03, 2010 at 09:09:56AM +0100, Ruben de Groot wrote: > >> > > I'm going to get this kern.timecounter sysctl from the system booted > >> > > with a 7.x livecd > >> > > this evening. But really, I think this is a regression. Even if this > >> > > system is the only > >> > > one known to be affected (which I sincerely doubt). > >> > > >> > You can force a timecounter choice by setting it in /boot/loader.conf. > >> > I would recommend choosing ACPI-safe on your system to see if that > >> > improves things: > >> > > >> > kern.timecounter.hardware=ACPI-safe > >> > >> Thanks, that solved my issue. Allthough for correctness I must add that > >> this line > >> must be put in /etc/sysctl.conf; it does nothing in loader.conf. > >> Also the sysctl can be run in multiuser and immediately fixed the problem. > > > > Ah, I thought it was a loader tunable, not a sysctl tunable. My > > apologies! Yes, sysctl.conf is the correct place for this. > > > >> One question remains: why did this suddenly become a problem in FreeBSD 8 > >> and not > >> in FreeBSD 7. > > > > That would be a question for the people who decided upon the timecounter > > priorities in FreeBSD, since they're hard-coded (meaning: why HPET is > > chosen above ACPI-safe). This may have changed between RELENG_7 and > > RELENG_8; I simply don't know. It would be easy to verify on your > > system of course (just boot a FreeBSD 7 LiveCD and provide the output > > from sysctl kern.timecounter). > > > > Another possibility could be that RELENG_7 was finding ACPI-fast, > which is rated above HPET. I'm not sure why some machines get > ACPI-fast and some get ACPI-safe - I think ACPI-fast is tested at boot > up, and if the measurements are not consistent, it disables ACPI-fast > and uses ACPI-safe instead, which is then ignored when HPET is > available.
I believe that question got answered last month: Q: http://lists.freebsd.org/pipermail/freebsd-stable/2010-February/055056.html A: http://lists.freebsd.org/pipermail/freebsd-stable/2010-February/055057.html A: http://lists.freebsd.org/pipermail/freebsd-stable/2010-February/055071.html A: http://lists.freebsd.org/pipermail/freebsd-stable/2010-February/055158.html -- | Jeremy Chadwick j...@parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB | _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
