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Subject: Re: hackbench regression with kernel 2.6.32-rc1
From: Mike Galbraith <efault@gmx.de>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>,
       LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>
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Date: Mon, 12 Oct 2009 16:33:52 +0200
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On Mon, 2009-10-12 at 16:21 +0200, Peter Zijlstra wrote:

> Mike, did we ever figure out _why_ NEXT_BUDDY introduced latencies?

No, I haven't gotten around to poking at that yet.  I'll try that x264
thing, IIRC, NEXT_BUDDY hurt it pretty badly.

> Buddies shouldn't make latencies worse than regular while(1); loops
> would.

Yeah, no idea what's going wrong.

	-Mike