Re: Posix realtime thread scheduling latencies

[Leon Woestenberg <leon.woestenberg@xxxxxxxxx>]

Hello Daniel,

On Mon, Aug 3, 2009 at 3:47 PM, Daniel
Himmelein<daniel.himmelein@xxxxxxxxxxxxxx> wrote:
> I observed some strange behaviour with scheduling realtime pthreads on
> Linux (2.6.26, Freescale i.MX31 (ARM11) board).
>
1) It seems you need to add the PREEMPT_RT patch which enables
PREEMPT_RT rather than PREEMPT.

Hard real-time scheduling is not yet fully upstream in the Linux
kernel, and you seem to be using a part of the API that is devoted to
real-time scheduling, but for now, will only schedule in a
soft-real-time manner.

http://rt.wiki.kernel.org/index.php/CONFIG_PREEMPT_RT_Patch

2) If you do have that patch applied, make sure your .config uses
CONFIG_PREEMPT_RT

Regards,

Leon.

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