Re: clock works slowly when I change CPU speed

Thorsten Greiner wrote:
> * Bob Fleck <bob_at_securesoftware.com> [2003-08-15 22:46]:
> > So, what should be done to restore the proper behavior of the
> > timekeeping on these systems?
> 
> $ dmesg | grep counter
> Timecounter "i8254"  frequency 1193182 Hz
> Timecounter "ACPI-fast"  frequency 3579545 Hz
> Timecounter "TSC"  frequency 1595302164 Hz
> $ sysctl -w kern.timecounter.hardware=i8254
> 
> Fixes the problem for me. I suspect you should set this in
> /etc/sysctl.conf to enable it permanently.

I suspect that systems where ACPI indicates that the clock speed
may change as a result of power management events should set this
automatically so people don't have to hack up their system with
sysctl's just to get things to work, when it's well known that
the system selecting TSC by default on systems with a variable
processor speed will experience problems otherwise.

I'm guessing what changes in the patches is that the default for
preferred clock changed to the wrong thing.

-- Terry