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Date: Thu, 13 Oct 2011 16:08:54 -0400 (EDT)
Message-Id: <20111013.160854.1765661520007592071.davem@davemloft.net>
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Subject: Re: [PATCH v7 0/8] Request for inclusion: tcp memory buffers
From: David Miller <davem@davemloft.net>
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From: Glauber Costa <glommer@parallels.com>
Date: Fri, 14 Oct 2011 00:05:58 +0400

> On 10/14/2011 12:00 AM, David Miller wrote:
>> That imposes a new non-trivial cost, in fast paths, even when people
>> do not use your feature.
> Well, there is a cost, but all past submissions included round trip
> benchmarks.
> In none of them I could see any significant slowdown.

Did you try millions of sockets doing all kinds of different accesses?

Did you check the nanosecond latency of operations over loopback so
that the real cost of you change can be isolated and thus measured
properly?