From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Mon, 1 Dec 2014 08:29:53 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Message-ID: <20141201072953.GP2964@hermes>
References: <314E5ECDAA86314791309FA670550F89C9C4C7FA@SINTEFEXMBX05.sintef.no>
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Subject: Re: [Xenomai] Method for measuring CPU idle time in Xenomai?
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To: Terje =?utf-8?Q?Fr=C3=B8ysa?= <Terje.Froysa@sintef.no>
Cc: "xenomai@xenomai.org" <xenomai@xenomai.org>

On Fri, Nov 28, 2014 at 06:00:27PM +0000, Terje Frøysa wrote:
> Dear Sirs,
> 
> I have now four real time processes running and a mix of rt-tasks and Linux tasks.
> In a pure Linux environment, CPU idle time can be estimated by:
> 
> awk '{print ($2*100)/$1 " % idle over "$1/60 " min"}' /proc/uptime
> 
> Question:
> Will this method apply in an Xenomai environment too?
> If not, is there any method that will apply?

I am not sure Linux load average calculations stay valid with
Xenomai running. For Xenomai tasks, /proc/xenomai/stat will give you
the cpu consumption, but all linux activities will appear as the
root task, whether idle or not.

-- 
					    Gilles.