From: Mark Hounschell <dmarkh@cfl.rr.com>
To: Vladimir Cotfas <vladc@mantatest.com>
Cc: linux-rt-users@vger.kernel.org, Scott Gilbertson <scottg@mantatest.com>
Subject: Re: Latency Problems with 2.6.31/PREEMPT_RT on a 1.2GHz Celeron
Date: Sat, 19 Dec 2009 06:34:00 -0500 [thread overview]
Message-ID: <4B2CBA28.1030405@cfl.rr.com> (raw)
In-Reply-To: <4B2BB45A.9040909@mantatest.com>
On 12/18/2009 11:56 AM, Vladimir Cotfas wrote:
> All,
>
> I have a a driver that must process an interrupt every 100 uS without
> missing any. I am having latency issues and I am looking for some help
> debugging my problem.
>
You'll probably never get this working reliably with the RT kernel. Latencies
are more deterministic with the RT kernel but slightly higher. You'll have better
luck with a vanilla kernel running your app in run level 4. And then even better
luck running on an SMP machine isolating your process and IRQ to a single
processor. And stay away from the VGA console. You have better luck with
faster hardware too.
Mark
next prev parent reply other threads:[~2009-12-19 11:34 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <abe060d60912171537j10fe194r5f0cd1aca85475df@mail.gmail.com>
2009-12-18 16:56 ` Latency Problems with 2.6.31/PREEMPT_RT on a 1.2GHz Celeron Vladimir Cotfas
2009-12-19 11:34 ` Mark Hounschell [this message]
2009-12-21 9:16 ` Nikita V. Youshchenko
2009-12-21 10:05 ` Mark Hounschell
2009-12-21 20:36 ` Carsten Emde
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