From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Sinisa Denic <sinisa.denic@domain.hid>
Cc: Xenomai help <xenomai@xenomai.org>
Subject: Re: [Xenomai-help] ARM cached,non-cached memory
Date: Tue, 02 Mar 2010 15:32:06 +0100 [thread overview]
Message-ID: <4B8D2166.7080704@domain.hid> (raw)
In-Reply-To: <201003021527.30130.sinisa.denic@domain.hid>
Sinisa Denic wrote:
> Hi, last year working with xenomai 2.4.2-3 we met problem (BUG) with memory
> caching on ARM AT91sam9260 arch.
> Then we were advised using non-cached memory and we've used it till now,but in
> our next application it has big performace slow down effect and I'm
> interested is this BUG solved in latest 2.4.10 - xenomai
> Regards,Sinisa
No, this is not a BUG in Xenomai. It is an architectural BUG^H^Hehaviour
of ARMv5, they have a VIVT cache, which is the cause of these issues.
Alternatively to using non-cached memory, you can use cached memory, and
flush cache when needed. Beware however defining "when needed", may be
complicated.
A note: Xenomai 2.4.10 is not the latest, the latest is Xenomai 2.5.1
and it has a lot of performance improvements for ARM.
--
Gilles.
next prev parent reply other threads:[~2010-03-02 14:32 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-02 14:27 [Xenomai-help] ARM cached,non-cached memory Sinisa Denic
2010-03-02 14:32 ` Gilles Chanteperdrix [this message]
2010-03-02 15:31 ` Sinisa Denic
2010-03-02 18:42 ` Gilles Chanteperdrix
2010-03-06 10:42 ` Gilles Chanteperdrix
2010-03-08 7:58 ` Sinisa Denic
2010-03-08 13:52 ` Gilles Chanteperdrix
2010-03-08 14:59 ` Sinisa Denic
2010-03-08 15:13 ` Gilles Chanteperdrix
2010-03-08 15:34 ` Sinisa Denic
2010-07-11 11:32 ` Bosko Radivojevic
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