From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: John Sini <jhnsini@gmail.com>
Cc: xenomai@xenomai.org
Subject: Re: [Xenomai] Negative latencies
Date: Tue, 13 Jan 2015 21:39:58 +0100 [thread overview]
Message-ID: <20150113203958.GL21032@hermes.click-hack.org> (raw)
In-Reply-To: <CAPozGfnFbPgfhi-ennhT2Ba=HJqs25W3WWVewXjBVbo87D81iQ@mail.gmail.com>
On Tue, Jan 13, 2015 at 06:01:54PM +0100, John Sini wrote:
> Hello,
>
>
> I was trying to boot linux with Xenomai on the Zedboard from Xilinx. When I
> run the latency test I get negative values. I tried to calibrate my system
> by running the following
> echo 1 > /proc/xenomai/latency
>
>
> But then when I run
>
> cat latency - I get 0. I also get 0 if I put 2 or 3ns. If I put 4 i.e.
>
> echo 4 > /proc/xenomai/latency and then do:
>
> cat latency - I get 3.
>
> Is there a possibility to calibrate my system to 1ns? Can the calibration
> be done without echo 1 > /proc/xenomai/latency somehow in latency.c. Before
> doing any calibration latency that I get is 9498.
See:
https://xenomai.org/pipermail/xenomai/2007-May/009063.html
--
Gilles.
prev parent reply other threads:[~2015-01-13 20:39 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-13 17:01 [Xenomai] Negative latencies John Sini
2015-01-13 20:39 ` Gilles Chanteperdrix [this message]
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