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Date: Fri, 22 Feb 2002 11:44:10 -0800
From: Paul Jackson <pj@engr.sgi.com>
To: Ingo Molnar <mingo@elte.hu>
cc: Erich Focht <efocht@ess.nec.de>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Matthew Dobson <colpatch@us.ibm.com>,
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        Linus Torvalds <torvalds@transmeta.com>
Subject: Re: [Lse-tech] Re: [PATCH] O(1) scheduler set_cpus_allowed for
 non-current tasks
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On Fri, 22 Feb 2002, Ingo Molnar wrote:
> 
> well, how do you migrate the task from an IRQ context?

Let it remove itself, in due time.

> even if it worked, this adds a 1/(2*HZ) average latency to the migration.
> I wanted to have something that is capable of migrating tasks 'instantly'.

That's the key question, from my perspective.

I was not aware of any need for instant migration, and to
the best of my knowledge, a clock tick latency was just fine.
But if your intuition suggests its worth supporting instant
migration, go for it.

The main concern I had with Erich Focht's patches that also
attempted instant migration was that Ingo wouldn't agree.
Somehow, I don't think that concern applies for your patches.

Thanks, Ingo!  I'm delighted with the outcome.

-- 
                          I won't rest till it's the best ...
                          Programmer, Linux Scalability
                          Paul Jackson <pj@sgi.com> 1.650.933.1373

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