To: "H.K. Jerry Chu" <hkjerry.chu@gmail.com>
Subject: Re: [PATCH] tcp: Expose the initial RTO via a new sysctl.
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Date: Fri, 20 May 2011 13:00:02 +0200
From: Hagen Paul Pfeifer <hagen@jauu.net>
Cc: David Miller <davem@davemloft.net>, <tsunanet@gmail.com>,
        <kuznet@ms2.inr.ac.ru>, <pekkas@netcore.fi>, <jmorris@namei.org>,
        <yoshfuji@linux-ipv6.org>, <kaber@trash.net>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
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On Fri, 20 May 2011 03:27:37 -0700, "H.K. Jerry Chu" wrote:

Hi Jerry

> Not sure how our various parameter tuning proposals deviate from the
"TCP
> over everything" principle?

For our environment it hurts because we _always_ have an initial RTO >1. I
understand and accept that 98% will benefit of this modification, no doubt
Jerry! Try to put yourself in our situation: imaging a proposal of an init
RTO modification to 0.5 seconds. Maybe because 98% of Internet traffic is
now localized and the RTO is average now 0.2 seconds. Anyway, this will
penalize your network always and this will be the situation for one of my
customer. I can live with that, I see the benefits for the rest of the
world. But I am happy to see a knob where I can restore the old behavior.
Maybe some other environments will benefit from a even lower or higher
initial RTO.

Hagen
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