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Date: Tue, 23 Sep 2008 10:25:16 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] Interrupt latency questions
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To: Antonio Del Cinque <adelcinque@domain.hid>
Cc: xenomai@xenomai.org

Antonio Del Cinque wrote:
> Thank you,
> I think your considerations are the right ones.
> 
> The DMA controller is not generating any interrupt, so I assume it is not
> actually working. I'm trying to verify that the jitter is caused by
> cache/TLB misses. I don't have much reference on how to lock the cache, so
> I'll just try to have the cache dirty in any other way to see if it causes
> the same jitter.

A good way to do this is to use the cache calibrator:
http://homepages.cwi.nl/~manegold/Calibrator/

-- 
                                                 Gilles.