From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15591 invoked by alias); 9 Jul 2002 16:13:11 -0000 Mailing-List: contact ecos-discuss-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@sources.redhat.com Received: (qmail 15544 invoked from network); 9 Jul 2002 16:13:10 -0000 Received: from unknown (HELO conn.mc.mpls.visi.com) (208.42.156.2) by sources.redhat.com with SMTP; 9 Jul 2002 16:13:10 -0000 Received: from grante.comtrol.com (isis.visi.com [209.98.98.8]) by conn.mc.mpls.visi.com (Postfix) with SMTP id 6B4088201 for ; Tue, 9 Jul 2002 11:13:09 -0500 (CDT) Received: (qmail 962 invoked by uid 500); 9 Jul 2002 16:16:45 -0000 Date: Tue, 09 Jul 2002 09:13:00 -0000 From: Grant Edwards To: Mark Salter Cc: gary@chez-thomas.org, ecos-discuss@sources.redhat.com Message-ID: <20020709111644.A856@visi.com> References: <20020708181640.A31952@visi.com> <1026170335.15020.1426.camel@hermes.chez-thomas.org> <20020708183316.A31984@visi.com> <200207090136.g691aOf18638@deneb.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2i In-Reply-To: <200207090136.g691aOf18638@deneb.localdomain>; from msalter@redhat.com on Mon, Jul 08, 2002 at 09:36:24PM -0400 Subject: Re: [ECOS] TCP stack not delaying/piggybacking ACKs? X-SW-Source: 2002-07/txt/msg00106.txt.bz2 On Mon, Jul 08, 2002 at 09:36:24PM -0400, Mark Salter wrote: > >>>>> Grant Edwards writes: > > > I've been browsing around the sources and haven't quite figured > > out how it's supposed to work. I do have the TCP_NODELAY flag > > set on the socket, but I don't know if that has anything to do > > with it. That is easy enough to test. > > Try turning it off. TCP_NODELAY tells the stack to send ACKs without > waiting a bit for a possible packet to piggyback on. Turning off TCP_NODELAY doesn't make any difference. ACKs are still sent out immediately. I've read through the TCP stack sources and AFAICT, the only place where NODELAY is checked is when tcp_output is trying to figure out how much data to send. [This agrees with my reading of Stevens.] Why ACKs aren't being delayed is apparently a different issue... -- Grant Edwards grante@visi.com -- Before posting, please read the FAQ: http://sources.redhat.com/fom/ecos and search the list archive: http://sources.redhat.com/ml/ecos-discuss