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Re: TSC vs. HPET timecounter priority
> On Sun, Aug 12, 2012 at 08:14:50PM -0700, Erik Fair wrote:
>> Until something is written and committed, I suggest an easy change in
>> "quality" for HPET to make it preferred to TSC if both are present.
> It took me also a little while to recognize that i have a timecounter issue.
> There was no error message from the ntpd that the system has not a stable
> clock. Another system didn't syncronize the time with ntp and so i had to
> hunt down what is wrong. My resolution was to change sysctl.conf to switch
> from tsc to hpet but that takes to find the issue.
> What about the following patch?
> tc_quality for hpet is set to 2000 so it would have a higher priority.
> Using 1500 leave some room for other implementations to have a higher
> priority then tsc.
please take a look at tsc_tc_init.
> Index: tsc.c
> RCS file: /cvsroot/src/sys/arch/x86/x86/tsc.c,v
> retrieving revision 1.30
> diff -b -u -r1.30 tsc.c
> --- tsc.c 8 Aug 2011 17:00:23 -0000 1.30
> +++ tsc.c 13 Aug 2012 05:48:41 -0000
> @@ -59,7 +59,7 @@
> .tc_get_timecount = tsc_get_timecount,
> .tc_counter_mask = ~0U,
> .tc_name = "TSC",
> - .tc_quality = 3000,
> + .tc_quality = 1500,
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