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Subject: Re: RFC for a new Scheduling policy/class in the Linux-kernel
From: Raistlin <raistlin@linux.it>
To: Chris Friesen <cfriesen@nortel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
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On Tue, 2009-07-14 at 12:24 -0600, Chris Friesen wrote:
> > - that A is actually blocked, as said before;
>=20
> Why does it make any difference that A is blocked rather than busy
> waiting?  In either case A cannot make forward progress.
>=20
I think it's not a problem of A, but of the overall schedule, from a
system predictability perspective.

Anyway, we are still evaluating what, if any could the issues be.

> > - that A's budget is not diminished.
>=20
> If we're running B with A's priority, presumably it will get some amount
> of cpu time above and beyond what it would normally have gotten during a
> particular scheduling interval. =20
>
Right...

> Perhaps it would make sense to charge B
> what it would normally have gotten, and charge the excess amount to A?
>=20
Mmm.. That's right, but I'm not sure I get what happen while executing
C... Anyway, it seems to me that we are getting closer to each other
point of view... let's keep staying in touch! :-D

Regards,
Dario

--=20
<<This happens because I choose it to happen!>> (Raistlin Majere)
----------------------------------------------------------------------
Dario Faggioli, ReTiS Lab, Scuola Superiore Sant'Anna, Pisa  (Italy)

http://blog.linux.it/raistlin / raistlin@ekiga.net /
dario.faggioli@jabber.org

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