Re: Timekeeping hosed by factor 3, high lapic[01] interrupt rates

From: John Baldwin <jhb_at_FreeBSD.org>
Date: Thu, 23 Jun 2005 17:14:39 -0400
On Thursday 23 June 2005 04:58 pm, Jens Schweikhardt wrote:
> John et al,
>
> On Wed, Jun 22, 2005 at 10:57:47AM -0400, John Baldwin wrote:
> # On Tuesday 21 June 2005 03:51 pm, Jens Schweikhardt wrote:
> # > John,
> # >
> # > # > See
> # > http://lists.freebsd.org/pipermail/freebsd-current/2005-May/050210.html
> # > # > for the whole thread.
> # > #
> # > # I did glance over it, but I don't really have time to read every
> e-mail # > on # current_at_ in detail. :(  Do you have verbose dmesg's for
> both cases? # > If so, # can you get the 'lapic: Divisor' lines from each
> boot? # >
> # > Sure, they are the same:
> # > lapic: Divisor 2, Frequency 99829738 hz
> # >
> # > It appears Chris Gilbert has the same problem, see "Timekeeping gone
> # > whack in 6-CURRENT" on this list.
> #
> # Ok, this is weird.  Does this happen if you disable SMP via
> # 'kern.smp.disabled=1' from the loader?
>
> No, with "set kern.smp.disabled=1" at the loader prompt,
> timekeeping is ok and vmstat -i displays
>
> interrupt                          total       rate
> irq1: atkbd0                         684          3
> irq13: npx0                            1          0
> irq14: ata0                           63          0
> irq15: ata1                          109          0
> irq18: em0                            27          0
> irq24: ahd0                        23192        106
> irq25: ahc0                           16          0
> lapic0: timer                     430979       1986
> Total                             455071       2097
>
> Regards,
>
> 	Jens

Ok.  What timecounter does your UP kernel use, and does your UP kernel break 
if you change the timecounter to i8254?

-- 
John Baldwin <jhb_at_FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org
Received on Thu Jun 23 2005 - 20:12:44 UTC

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