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Subject: Re: [RFC][PATCH 18/22] sched: add reclaiming logic to -deadline
 tasks
From: Raistlin <raistlin@linux.it>
To: "James H. Anderson" <anderson@cs.unc.edu>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@elte.hu>,
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On Mon, 2010-11-15 at 13:37 -0500, James H. Anderson wrote:
> Sorry for the delayed response... I think I must have inadvertently=20
> deleted this
>
NP. Hope it's not my fault, due to GPG and stuff... :-)

> If you're talking about our most recent "stochastic" paper, it is about=20
> supporting
> soft real-time task systems on a multiprocessor where resource=20
> reservations are
> used. =20
>
Actually, we were talking about the previous one, which (if I got it
well) didn't include reservations, and that's why we were wondering how
to integrate it in the scheduler (which _is_ reservation based).

Now that this one is out, going for it simply solves all our issues,
also considering that it says something very similar to what we (Pisa
guys :-D) are familiar with, since we investigated this stuff too
sometime ago (actually, Luca did).

> However, such methods would be easy to incorporate. =20
>
I think it really should be... Actually, I'm under the impression that
we don't even need variance/std-dev of the execution time to be part of
the interface, do we?

> I gathered there was
> some confusion about whether we were using resource reservations.  Such
> reservations are actually crucial for our analysis as they allow=20
> independence to be assumed across tasks.
>
Yes, as I said, this was because we were looking at first paper. Now we
got it, thanks a lot for clarifying! :-)

> I hope this helps.
>=20
A lot, thanks again.

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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