Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS]

Peter Williams
2007-04-17T08:00:17Z

William Lee Irwin III wrote:
> On Tue, Apr 17, 2007 at 04:34:36PM +1000, Peter Williams wrote:
>> This doesn't make any sense to me.
>> For a start, exact simultaneous operation would be impossible to achieve
>> except with highly specialized architecture such as the long departed
>> transputer. And secondly, I can't see why it's necessary.
>
> We're not going to make any headway here, so we might as well drop the
> thread.

Yes, we were starting to go around in circles weren't we?

>
> There are other things to talk about anyway, for instance I'm seeing
> interest in plugsched come about from elsewhere and am taking an
> interest in getting it into shape wrt. various design goals therefore.
>
> Probably the largest issue of note is getting scheduler drivers
> loadable as kernel modules. Addressing the points Ingo made that can
> be addressed are also lined up for this effort.
>
> Comments on which directions you'd like this to go in these respects
> would be appreciated, as I regard you as the current "project owner."

I'd do scan through LKML from about 18 months ago looking for mention of
runtime configurable version of plugsched. Some students at a
university (in Germany, I think) posted some patches adding this feature
to plugsched around about then.

I never added them to plugsched proper as I knew (from previous
experience when the company I worked for posted patches with similar
functionality) that Linux would like this idea less than he did the
current plugsched mechanism.

Unfortunately, my own cache of the relevant e-mails got overwritten
during a Fedora Core upgrade (I've since moved /var onto a separate
drive to avoid a repetition) or I would dig them out and send them to
you. I'd provided with copies of the company's patches to use as a
guide to how to overcome the problems associated with changing
schedulers on a running system (a few non trivial locking issues pop up).

Maybe if one of the students still reads LKML he will provide a pointer.

Peter
--
Peter Williams pwil3058@bigpond.net.au

"Learning, n. The kind of ignorance distinguishing the studious."
-- Ambrose Bierce