From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: Socket buffer sizes with autotuning Date: Fri, 25 Apr 2008 00:21:08 +0200 Message-ID: <87ej8uyjvv.fsf@basil.nowhere.org> References: <480E8523.4030007@hp.com> <1e41a3230804221917m4af32ed9ice8225c943d3ffa2@mail.gmail.com> <20080422.205945.229828014.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: johnwheffner@gmail.com, rick.jones2@hp.com, netdev@vger.kernel.org To: David Miller Return-path: Received: from smtp-out04.alice-dsl.net ([88.44.63.6]:38519 "EHLO smtp-out04.alice-dsl.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754363AbYDXWVL (ORCPT ); Thu, 24 Apr 2008 18:21:11 -0400 In-Reply-To: <20080422.205945.229828014.davem@davemloft.net> (David Miller's message of "Tue, 22 Apr 2008 20:59:45 -0700 (PDT)") Sender: netdev-owner@vger.kernel.org List-ID: David Miller writes: >> What is your interface txqueuelen and mtu? If you have a very large >> interface queue, TCP will happily fill it up unless you are using a >> delay-based congestion controller. > > Yes, that's the fundamental problem with loss based congestion > control. If there are any queues in the path, TCP will fill them up. That just means Linux does too much queueing by default. Perhaps that should be fixed. On Ethernet hardware the NIC TX queue should be usually sufficient anyways I would guess. Do we really need the long qdisc queue too? -Andi