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Date: Sun, 26 Sep 2004 09:52:18 +0200
From: Peter Holm <peter@holm.cc>
To: Julian Elischer <julian@elischer.org>
Message-ID: <20040926075218.GA85983@peter.osted.lan>
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cc: peter@holm.cc
cc: "freebsd-arch@freebsd.org" <freebsd-arch@freebsd.org>
cc: Stephan Uphoff <ups@tree.com>
Subject: Re: scheduler (sched_4bsd) questions
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On Sat, Sep 25, 2004 at 08:50:45PM -0700, Julian Elischer wrote:
> Stephan Uphoff wrote:
> 
> >>Maybe something brutal like:
> >>	if ((curthread->td_ksegrp == kg) &&
> >>	   (td->td_priority > curthread->td_priority))
> >>		curthread->td_flags |= TDF_NEEDRESCHED;
> >>
> >>in setrunqueue for
> >>the else case of "if (kg->kg_avail_opennings > 0)"
> >>would do the trick (without preemption) for the easy but probably more
> >>common cases?
> >>
> >>Maybe I can find some time next week to think about a clean
> >>fix. I find it always helpful having a small task in mind while reading
> >>source code.
> >
> >
> >I wrote a fix that should cover all cases.
> >However I would like to test it a little bit before posting the patch.
> >Is there any multi-threaded kernel torture program that you can
> >recommend?
> 
> 
> Peter Holm (CC'd) has a really cool set of torture tests.
> he has also seen all sorts of failures others have not (yet) triggered. :-)
> 
> I'm 'busy" for the next couple of weeks so you may want to communicate 
> directly with him and see if you and he together can figure out some of the 
> things he's
> been seeing :-)
> 
> his tests are at:
> http://www.holm.cc/stress/src/stress.tgz
> 
> >
> >Thanks
> >
> >	Stephan
> >

I'll be glad to test any patches.
-- 
Peter Holm