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From: David Xu <davidxu@freebsd.org>
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Date: Mon, 9 Oct 2006 07:39:45 +0800
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Cc: Kip Macy <kmacy@fsmware.com>, Ivan Voras <ivoras@fer.hr>
Subject: Re: [PATCH] MAXCPU alterable in kernel config - needs testers
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On Monday 09 October 2006 06:55, Kip Macy wrote:
> > Any word on how will they handle migration of threads across sockets (or
> > will it be OS's job)? Judging from T1 architecture, I think such event
> > would create a very large performance penalty, but I'm not an expert.
>
> It is the job of the OS to take locality into account in thread
> scheduling. Moving between chips You'll just lose the L2 cache locality
> just as you would on a normal SMP.
>
>
> 			-Kip
Current MD code does not provide useful CPU topology data structure,
it is impossible to write a locality aware scheduler for sun4v and other
NUMA architectures.

David Xu