Date: Thu, 22 Jan 2004 14:50:26 -0500
From: timothy parkinson <t@timothyparkinson.com>
To: john stultz <johnstul@us.ibm.com>
Cc: hauan@cmu.edu, Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: 2.6.1 "clock preempt"?
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	Linux Kernel <linux-kernel@vger.kernel.org>
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well, it does *say* the following:

  ..... host bus clock speed is 133.0266 MHz.
  checking TSC synchronization across 2 CPUs: passed.
  Starting migration thread for cpu 0

is there a good way to check IDE PIO?

timothy


On Thu, Jan 22, 2004 at 11:42:35AM -0800, john stultz wrote:
> On Thu, 2004-01-22 at 11:37, timothy parkinson wrote:
> > hi john,
> > 
> > i think this sounds like the same issue that i've been seeing with 2.5/2.6
> > kernels for a while now.  smp kernel on a dual PIII machine without preempt.
> > 
> > after running for a while the "losing ticks" shows up in dmesg, and the system
> > loses a lot of time.  load seems to make it worse, so that just might be the
> > trigger.
> > 
> > i'll try that one-liner as well when i get a chance - you said that if the
> > system still loses time, that narrows it down to hardware, yes?
> 
> Well, not necessarily hardware, but it narrows it down to something
> blocking interrupts for way too long. IDE PIO for example seems to be a
> likely culprit. Another possibility on SMP systems is your cpu TSCs not
> being in sync.
> 
> thanks
> -john
> 
> 
> 
-
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