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Date: Thu, 27 Sep 2012 12:20:50 +0200
From: Borislav Petkov <bp@alien8.de>
To: david@lang.hm
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
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        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>,
        Suresh Siddha <suresh.b.siddha@intel.com>
Subject: Re: 20% performance drop on PostgreSQL 9.2 from kernel 3.5.3 to
 3.6-rc5 on AMD chipsets - bisected
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On Thu, Sep 27, 2012 at 12:17:22AM -0700, david@lang.hm wrote:
> It seems to me that trying to figure out if you are going to
> overload the L2 is an impossible task, so just assume that it will
> all fit, and the worst case is you have one balancing cycle where
> you can't do as much work and then the normal balancing will kick in
> and move something anyway.

Right, and this implies that when the load balancer runs, it will
definitely move the task away from the L2. But what do I do in the cases
where the two tasks don't overload the L2 and it is actually beneficial
to keep them there? How does the load balancer know that?

-- 
Regards/Gruss,
    Boris.