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Date: Wed, 3 Sep 2014 13:32:42 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Jason Low <jason.low2@hp.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>, Paul Turner <pjt@google.com>,
        Ingo Molnar <mingo@kernel.org>, Ben Segall <bsegall@google.com>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] sched: Reduce contention in update_cfs_rq_blocked_load
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On Tue, Sep 02, 2014 at 12:41:24AM -0700, Jason Low wrote:
> On Mon, 2014-09-01 at 14:55 +0200, Peter Zijlstra wrote:
> > But yes, unbounded errors here are a problem, sure relaxing the updates
> > makes things go fast, they also make things go skew.
> 
> Okay. In that case, would you like to take our original patch which
> avoids unnecessary updates?

This seems a safe patch; yes I'll queue it while we think of smarter
things :-)