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Date: Sat, 11 Feb 2012 19:05:18 +0200
From: Andriy Gapon <avg@FreeBSD.org>
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To: Alexander Motin <mav@FreeBSD.org>, freebsd-hackers@FreeBSD.org
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Subject: Re: [RFT][patch] Scheduling for HTT and not only
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on 11/02/2012 15:35 Andriy Gapon said the following:
> It seems that on modern CPUs the caches are either inclusive or some smart "as
> if inclusive" caches.  As a result, if two cores have a shared cache at any
> level, then it should be relatively cheap to move a thread from one core to the
> other.  E.g. if logical CPUs P0 and P1 have private L1 and L2 caches and a
> shared L3 cache, then on modern processors it should be much cheaper to move a
> thread from P0 to P1 than to some processor P2 that doesn't share the L3 cache

Having read this paper
http://www.cs.uwaterloo.ca/~brecht/courses/856/Possible-Readings/multicore/cache-performance-x86-2009.pdf
I think that I have been too optimistic about the smartness of caches in some
processors...

-- 
Andriy Gapon