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Date: Mon, 20 Jun 2011 16:25:00 +0100
From: Jakub Nowacki <j.s.nowacki@domain.hid>
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Subject: Re: [Xenomai-help] Xenomai on i7-870
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: Xenomai help <xenomai@xenomai.org>

On 06/20/2011 04:02 PM, Gilles Chanteperdrix wrote:
> To make proper benchmarks, you should:
> - let the latency run long
> - provide some load, you can use the dohell script in xenomai-head to
> generate the load.
>
I've generated a load using 'dd if=/dev/zero of=/dev/null' one for each 
core (8 in total), which is roughly the way how xeno-test does it. The 
test was running for 30 min, which is not very long but I should see the 
long latencies by that time, I think at least.

> That said, having some spikes is not abnormal. The real question is to
> know whether the latencies your get are sufficient for your application.
>
Well, I think it should be OK for peak latencies < 20 us, that is what 
I'm getting now.

>> ioctl(RTTST_RTIOC_SWTEST_CREATE_KTASK): Cannot allocate memory
>
> You have to increase CONFIG_XENO_OPT_SYS_STACKPOOLSZ.
>
It is 128 Kb now. Should it be more? Is there any (thumb) rule for this 
value?

Best wishes,

Jakub