From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH] TCP_FAILFAST: a new socket option to timeout/abort a connection quicker Date: Tue, 24 Aug 2010 08:44:22 +0200 Message-ID: <1282632262.2378.1681.camel@edumazet-laptop> References: <1282630819-23104-1-git-send-email-hkchu@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: ilpo.jarvinen@helsinki.fi, davem@davemloft.net, netdev@vger.kernel.org To: "H.K. Jerry Chu" Return-path: Received: from mail-wy0-f174.google.com ([74.125.82.174]:34692 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751980Ab0HXGo2 (ORCPT ); Tue, 24 Aug 2010 02:44:28 -0400 Received: by wyb35 with SMTP id 35so75584wyb.19 for ; Mon, 23 Aug 2010 23:44:27 -0700 (PDT) In-Reply-To: <1282630819-23104-1-git-send-email-hkchu@google.com> Sender: netdev-owner@vger.kernel.org List-ID: Le lundi 23 ao=C3=BBt 2010 =C3=A0 23:20 -0700, H.K. Jerry Chu a =C3=A9c= rit : > From: Jerry Chu >=20 > This is a TCP level socket option that takes an unsigned int to speci= fy > how long in ms TCP should resend a lost data packet before giving up > and returning ETIMEDOUT. The normal TCP retry/abort timeout limit sti= ll > applies. In other words this option is only meant for those applicati= ons > that need to "fail faster" than the default TCP timeout. The latter > may take upto 20 minutes in a normal WAN environment. >=20 > The option is disabled (by default) when set to 0. Also it does not > apply during the connection establishment phase. >=20 > Signed-off-by: H.K. Jerry Chu TCP_FAILFAST might be misleading. It reads as a boolean option, while its an option to cap the timeout, with a time unit, instead of the usua= l "number of retransmits". Its also funny you dont ask for a default value, given by a sysctl tunable ;)