Timecounter configuration [Was: Dell Latitude 610 CPU clock rate degrading (debug info included)]

[Alexandre "Sunny" Kovalenko]

On Wed, 2004-07-21 at 14:34, Nate Lawson wrote:
> Ted Faber wrote:
> > On Tue, Jul 20, 2004 at 12:00:59PM -0700, Nate Lawson wrote:
> > 
> >>Ted Faber wrote:
> >>>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
> >>>helped.
> >>
> >>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
> > curious).
> 
> When running without ACPI, you should use the i8254 timecounter.  Switch 
> it with this command (or put it in /etc/sysctl.conf):
> 
> sysctl kern.timecounter.hardware="i8254"

While we are on the subject, would this work for those of us who have
acpi timer broken:

acpi_timer0: couldn't allocate I/O resource (port 0x808)
acpi_timer0 port 0x808-0x80b on acpi0
pmtimer0 on isa0

I have seen somebody else posting this problem before, but if you need
any details or want to try patch, I'll be glad to. Right now if I use
powernow_k7 to throttle, my clock slows down accordingly. Problem have 
started few weeks ago, however, acpi_timer.c did not change between
working and non-working kernel.

Alexandre "Sunny" Kovalenko.