From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Hannemann Subject: Re: [PATCH] TCP_FAILFAST: a new socket option to timeout/abort a connection quicker Date: Thu, 26 Aug 2010 09:12:24 +0200 Message-ID: <4C7613D8.2040705@nets.rwth-aachen.de> 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> <20100825225942.GA3190@hell> <3CD6E1F6-9143-43B9-A6D2-9B09F18C9C2E@nokia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Jerry Chu , Hagen Paul Pfeifer , Eric Dumazet , "ilpo.jarvinen@helsinki.fi" , "davem@davemloft.net" , "netdev@vger.kernel.org" To: Lars Eggert Return-path: Received: from slowhand.arndnet.de ([88.198.19.76]:44155 "EHLO mail.unitix.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751762Ab0HZHjh (ORCPT ); Thu, 26 Aug 2010 03:39:37 -0400 In-Reply-To: <3CD6E1F6-9143-43B9-A6D2-9B09F18C9C2E@nokia.com> Sender: netdev-owner@vger.kernel.org List-ID: Hi Lars, Am 26.08.2010 08:01, schrieb Lars Eggert: > On 2010-8-26, at 4:49, Jerry Chu wrote: > >> Yes on a 2nd look RFC5482 seems more complex than I originally thought, allowing >> many different combinations of local/adv/remote UTO... Are they really >> useful, e.g., >> why allowing USER_TIMEOUT to be different from ADV_UTO?? My original thought >> was the local UTO will always be the same as the one advertised to >> remote so only >> one API will be needed plus bunch of flags for ENABLED, CHANGEABLE... >> > > USER_TIMEOUT is what is locally used for a connection (i.e., takes into account what the remote peer advertised and what we'd like to use), while ADV_UTO is (only) what we'd like to use and are advertising. > > (Yes, we initially thought we could make the mechanism simpler, but then we started to think through all the corner cases...) > But from the application point of view it is enough to request a specific UTO as a socket option, (which will then get announced via ADV_UTO), right? Is there any reason, (besides local policy) to not abort the connection locally after the time the application specified via the above mentioned socket option? Best regards, Arnd