From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rick Jones Subject: Re: tbench wrt. loopback TSO Date: Wed, 05 Nov 2008 13:06:45 -0800 Message-ID: <49120AE5.302@hp.com> References: <20081105114900.GA18691@ioremap.net> <20081105.035454.87914782.davem@davemloft.net> <20081105.040943.03609283.davem@davemloft.net> <20081105130405.GA26435@ioremap.net> <4911EA97.8080101@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: Evgeniy Polyakov , David Miller , Netdev , efault@gmx.de, mingo@elte.hu, a.p.zijlstra@chello.nl, Herbert Xu To: =?ISO-8859-1?Q?Ilpo_J=E4rvinen?= Return-path: Received: from g1t0026.austin.hp.com ([15.216.28.33]:5447 "EHLO g1t0026.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751580AbYKEVG5 (ORCPT ); Wed, 5 Nov 2008 16:06:57 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: >>Ignoring the TSO case for a moment, if there is congestion and receiver >>window available and a user makes a > MSS send that isn't an integral >>multiple of the MSS, we don't delay the last subMSS segment do we? > > > Without TSO, only Nagle could prevent sending that submss portion, so the > answer depends on what the window in-flight consists of. I always thought that Nagle was supposed to be implemented as if it was on a user send() by user send() basis and not segment by segment, in which case no send() > MSS would be delayed by Nagle. rick jones