Dell Latitude 610 CPU clock rate degrading (debug info included)
faber at ISI.EDU
Wed Jul 21 10:20:48 PDT 2004
On Tue, Jul 20, 2004 at 12:00:59PM -0700, Nate Lawson wrote:
> Ted Faber wrote:
> >My Dell Latatude 610 is having its clock rate go from 1000 Mhz to 733
> >Mhz under -CURRENT that was cvsupped and installed yesterday. I'm
> >honestly not sure how long this has been happening, since I only got the
> >clock speed monitor (the one that runs under gkrellm) hooked up a couple
> >weeks ago. I hooked it up because the machine seemed slow. It had been
> >happening for a couple weeks at least.
> >The rate seems to change after using the CPU hard for a while - a big
> >compile, like make buildworld seems to do it, though even a few minutes
> >of compilation seems sufficient.
> >When the CPU speed changes I get a message in the logs saying
> >cpu0: Performance states changed
> >The state never seems to change back to a high performance one. I've
> >configured the BIOS not to do power management with the AC connected,
> >and this happens with the AC connected.
> This transition is being done by the BIOS for passive cooling. We can't
> control it until the cpufreq driver is committed. When the system gets
> hot, the BIOS steps the processor down to 733 mhz but the timecounters have
> no way of knowing it happened.
Thanks for the info. If you've got a list of people to ping when the
cpufreq driver appears, put me on it. I'll be watching for the HEADSUP
in any case.
> >I tried booting without ACPI, but my time of day clock ran consistenty
> >slow - which might mean that the same degredation was occurring without
> >the OS readjusting for it. In any case it wasn't clear that no ACPI
> Same problem. What timecounter are you using? Switching away from TSC
> would help this.
With ACPI there's no clock skew problem, so that's how I've been
running. Just for my information, how might I switch timecounters? (It
sounds like it won't solve the problem to switch away from ACPI, but I'm
Thanks again for your quick response.
http://www.isi.edu/~faber PGP: http://www.isi.edu/~faber/pubkeys.asc
Unexpected attachment on this mail? See http://www.isi.edu/~faber/FAQ.html#SIG
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-acpi/attachments/20040721/d5a378bb/attachment.bin
More information about the freebsd-acpi