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From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Rob Wheeler <wheeler@domain.hid>
Cc: xenomai@xenomai.org
Subject: Re: [Xenomai-help] clock drift
Date: Wed, 14 Jan 2009 22:26:46 +0100	[thread overview]
Message-ID: <496E5896.7020801@domain.hid> (raw)
In-Reply-To: <894886ec0810012230j57e2f87n343a5b07bbdbd46@domain.hid>

Rob Wheeler wrote:
> Hello,
> 
> I was recently debugging a problem in our code base and tracked the
> issue down to differences between calling gettimeofday() from our
> non-realtime code and calling clock_gettime() from our realtime
> control loop.  A little poking around with Google led me to clocktest
> program in the Xenomai testsuite.  We are routinely seeing differences
> of around 4 minutes (~240 seconds) between gettimeofday() and
> clock_gettime() immediately after a reboot.  The clocks continue to
> drift apart (or together) at the rate of about 50us/s.

Hi Rob,

when chasing unrelated issues, I found what could be the cause of the
original 4 minutes difference. The bug is fixed in the svn repository. I
think it goes in the "very stupid bugs" category.

Well, tooks only 3 monthes...

Regards.

-- 
					    Gilles.


      parent reply	other threads:[~2009-01-14 21:26 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-10-02  5:30 [Xenomai-help] clock drift Rob Wheeler
2008-10-02  5:38 ` Gilles Chanteperdrix
     [not found]   ` <894886ec0810012258o67da00d7x2e3d54c7e601b470@domain.hid>
2008-10-02  6:05     ` Gilles Chanteperdrix
2008-10-02  7:45       ` Theo Veenker
2008-10-02  8:23         ` Gilles Chanteperdrix
2009-01-14 21:26 ` Gilles Chanteperdrix [this message]

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