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Date: Mon, 16 Mar 2009 17:10:08 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] xeno-test output
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To: Salvatore De Astis <dev.rinux@domain.hid>
Cc: xenomai@xenomai.org

Salvatore De Astis wrote:
> Hi at all!
> I tested the xenomai performance with xeno-test but  the "in-kernel
> periodic task" test mode shows me negative latencies, why?
> I've attached the report.
> Do you take a look at file and tell me if there is something wrong in
> my configuration, please?

That is because Xenomai timer anticipates, usually to get an almost null
latency for user-space tasks. So, you get negative latencies in
kernel-space. Fortunately, you can choose this (fixed) anticipation with
/proc/xenomai/latency.

-- 
                                                 Gilles.