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Date: Wed, 3 Sep 2014 11:30:08 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>,
        Mike Galbraith <umgwanakikbuti@gmail.com>, davem@davemloft.net,
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        Ingo Molnar <mingo@elte.hu>,
        Eliezer Tamir <eliezer.tamir@linux.intel.com>
Subject: Re: [PATCH net-next 2/2] net: exit busy loop when another process is
 runnable
Message-ID: <20140903093008.GC4783@worktop.ger.corp.intel.com>
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On Wed, Sep 03, 2014 at 02:58:33PM +0800, Jason Wang wrote:
> On 09/02/2014 06:24 PM, Peter Zijlstra wrote:
> The patch only try to improve the performance of busy read (and test
> results shows impressive changes). It does not change anything for busy
> poll. Considering there maybe two processes in one cpu, one is doing
> busy read and one is doing busy polling. This patch may in fact help the
> busy polling performance in this case.
> 
> It's good to discuss the ideas of busy poll together, but it was out of
> the scope of this patch. We can try to do optimization on top.

No thta's just wrong, blocked read and blocking select should behave the
same.