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Date: Fri, 11 Feb 2011 22:34:36 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] Clocksource tsc unstable
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To: Henri Roosen <henriroosen@domain.hid>
Cc: xenomai@xenomai.org

Henri Roosen wrote:
> As soon as I start our Xenomai application we get a Linux kernel
> message "Clocksource tsc unstable (delta = 305181188 ns)", after which
> it switches to the pit clock.
> 
> Will this have impact on Xenomai threads running in relaxed mode?
> 
> Is this normal behavior? Is this because primary domain interrupted
> the Linux clocksource watchdog for 305 ms? Should we disable the Linux
> clocksource wathdog so it keeps using the tsc?

Yes this is bad. But what you should do is that your application should
never interrupt linux for more than a clock tick, so, typically 10ms or
1ms, and it will not happen.

-- 
                                                                Gilles.