From mboxrd@z Thu Jan 1 00:00:00 1970 From: jamal Subject: Re: [PATCH] NET: Multiqueue network device support. Date: Mon, 11 Jun 2007 08:52:15 -0400 Message-ID: <1181566335.4043.231.camel@localhost> References: <1181082517.4062.31.camel@localhost> <4666CEB7.6030804@trash.net> <1181168020.4064.46.camel@localhost> <466D38CF.9060709@trash.net> <1181564611.4043.220.camel@localhost> <466D4284.1030004@trash.net> Reply-To: hadi@cyberus.ca Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: "Waskiewicz Jr, Peter P" , davem@davemloft.net, netdev@vger.kernel.org, jeff@garzik.org, "Kok, Auke-jan H" To: Patrick McHardy Return-path: Received: from py-out-1112.google.com ([64.233.166.183]:22452 "EHLO py-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751497AbXFKMwT (ORCPT ); Mon, 11 Jun 2007 08:52:19 -0400 Received: by py-out-1112.google.com with SMTP id a29so2595451pyi for ; Mon, 11 Jun 2007 05:52:18 -0700 (PDT) In-Reply-To: <466D4284.1030004@trash.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Mon, 2007-11-06 at 14:39 +0200, Patrick McHardy wrote: > jamal wrote: > > On Mon, 2007-11-06 at 13:58 +0200, Patrick McHardy wrote: > > > > Sure. Packets stashed on the any DMA ring are considered "gone to the > > wire". That is a very valid assumption to make. > > > I disagree, its obviously not true Patrick, you are making too strong a statement. Take a step back: When you put a packet on the DMA ring, are you ever going to take it away at some point before it goes to the wire? > and leads to the behaviour I > described. If it were true there would be no reason to use multiple > HW TX queues to begin with. In the general case, they are totaly useless. They are useful when theres contention/congestion. Even in a shared media like wireless. And if there is contention, the qdisc scheduler will do the right thing. cheers, jamal