Message-ID: <40E2F33C.90106@redhat.com>
Date: Wed, 30 Jun 2004 10:07:08 -0700
From: Ulrich Drepper <drepper@redhat.com>
Organization: Red Hat, Inc.
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To: Paul Davis <paul@linuxaudiosystems.com>
CC: Ingo Molnar <mingo@elte.hu>, linux-kernel@vger.kernel.org
Subject: Re: 2.6.X, NPTL, SCHED_FIFO and JACK
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Paul Davis wrote:

> this has me thinking. one of the major changes with NPTL is that all
> threads share the same PID. so how in the world do we ever set the
> scheduling policy of a single thread (as opposed to something
> identified by a pid_t) to SCHED_FIFO?

If you have to ask this question than it's no wonder you get erratic
behavior.  It means you haven't looked at the pthread interface at all.

Define a pthread_attr_t with the appropriate setting (with
pthread_attr_setschedparam etc) and create the thread (and use
pthread_attr_setinheritsched correctly).  Alternatively use
pthread_setschedparam on already running threads.

And use a recent enough nptl version.   Very early versions didn't have
any of the scheduler handling implemented.

-- 
➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖
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