From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hagen Paul Pfeifer Subject: Re: [PATCH] =?UTF-8?Q?TCP=5FFAILFAST=3A=20a=20new=20socket=20opti?= =?UTF-8?Q?on=20to=20timeout/abort=20a=20connection=20quicker?= Date: Wed, 25 Aug 2010 10:21:39 +0200 Message-ID: References: <1282630819-23104-1-git-send-email-hkchu@google.com> <1282632262.2378.1681.camel@edumazet-laptop> <4C737D15.5060400@nets.rwth-aachen.de> <423116d1d215b0fb3d1c966fb8167508@localhost> <4C73DE32.1030802@nets.rwth-aachen.de> <20100824162844.GA7889@nuttenaction> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Arnd Hannemann , Eric Dumazet , , , To: Jerry Chu Return-path: Received: from alternativer.internetendpunkt.de ([88.198.24.89]:43575 "EHLO geheimer.internetendpunkt.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751838Ab0HYIVq (ORCPT ); Wed, 25 Aug 2010 04:21:46 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 24 Aug 2010 15:13:44 -0700, Jerry Chu wrote: > On Tue, Aug 24, 2010 at 9:28 AM, Hagen Paul Pfeifer wrote: > So it looks like the user timeout can be used in either senario (shortening > or lengthening) and in both cases is a lower bound, i.e., the connection > should abort at or shortly after the specified user timeout. > > In this case does it make sense to combine the two? Will your TCP_UTO > patch be ready anytime soon? > > Again an alternative is to allow configuring tcp_retries2 and TCP_RTO_MAX > directly. I'm open to suggestion but we'd like to get something in sooner. Hello Chu! My Idea: you provide functionality to modify the user timeout. The interface should be generic enough to allow small as well as large - up to 22 days - values. This interface should be sufficient for you and later for me. Afterwards I provide an patch which apply on your groundwork. My patch handle TCP UTO specific functionality like TCP option protocol handling functionality, socket option, permissions, lower- and upper bounds, ... Did you check interactions with other TCP timers like keep-alive timer? Today in the evening I will focus on TCP Quick ACK modifications. After that I am in the Alps for vacation for 5 days. Later on I will work on the patch (the patch is in a good state, modification and testing should consume only 2 evenings - hopefully ;-). Cherry, is this ok for you? Hagen