From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: xenomai@xenomai.org
Subject: Re: [Xenomai-help] high latency with Intel Core 2 Duo
Date: Thu, 10 May 2007 18:28:39 +0200 [thread overview]
Message-ID: <46434837.9080605@domain.hid> (raw)
In-Reply-To: <46434561.2090309@domain.hid>
Jan Kiszka wrote:
> Karl Reichert wrote:
>
>>Hello,
>>
>> I'm using an Intel Core 2 Duo at work and an AMD XP3000+ at home. I installed Xenomai 2.3.1 with nearly same configuration at both and run the xeno-test. I get 10 times higher latency with Core 2 Duo. How is it possible? May the SMP be the reason?
>
>
> SMP surely increases latencies (more synchronisation overhead), but the
> tests you ran were also far to short for a thorough comparison. 2 us
> worst-case is far too good, even on high end. Also 20 us on loaded SMP
> boxes may not hold. Leave the test running for a longer period ("-T"
> parameter, I think).
You should configure the user-space libraries with the --enable-smp
option when configuring for SMP.
Also, did you compile a 32 bits or 64 bits kernel for the core 2 duo ?
If you think that you observe high latencies, check the TROUBLESHOOTING
file.
--
Gilles Chanteperdrix
next prev parent reply other threads:[~2007-05-10 16:28 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-05-10 12:09 [Xenomai-help] high latency with Intel Core 2 Duo Karl Reichert
2007-05-10 16:16 ` Jan Kiszka
2007-05-10 16:28 ` Gilles Chanteperdrix [this message]
2007-05-11 11:24 ` Karl Reichert
2007-05-11 13:23 ` Gilles Chanteperdrix
2007-05-14 11:20 ` Karl Reichert
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