From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Tue, 28 Apr 2015 10:32:43 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Message-ID: <20150428083243.GB1993@hermes.click-hack.org>
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 <20150428082434.GA1993@hermes.click-hack.org>
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Subject: Re: [Xenomai] Porting the I-pipe core to ARM big.LITTLE architecture
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To: Hongfei Cheng <hongfei@mperpetuo.com>
Cc: xenomai@xenomai.org

On Tue, Apr 28, 2015 at 10:24:34AM +0200, Gilles Chanteperdrix wrote:
> On Tue, Apr 28, 2015 at 01:08:12AM -0700, Hongfei Cheng wrote:
> > Searching the mailing list archives, I don't see mentioning of ARM's
> > big.LITTLE architecture. The list of the supported SoCs doesn't appear
> > to include any SoC based on ARM's big.LITTLE architecture.
> > 
> > Are there any special considerations for porting the I-pipe core to
> > such big.LITTLE architecture?
> 
> I would say this sounds like cpufreq:
> - migrating a task from an A15 to an A7 will have a huge impact on
> latencies
> - the speed difference will have a huge impact on the timings of the
> running tasks.

Note that xenomai never migrates a task from a cpu to another
automatically for the same reason.

-- 
					    Gilles.