Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031490AbWK3UzR (ORCPT ); Thu, 30 Nov 2006 15:55:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1031487AbWK3UzL (ORCPT ); Thu, 30 Nov 2006 15:55:11 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:9413 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1031458AbWK3UzH (ORCPT ); Thu, 30 Nov 2006 15:55:07 -0500 Date: Thu, 30 Nov 2006 21:54:28 +0100 From: Ingo Molnar To: David Miller Cc: johnpol@2ka.mipt.ru, nickpiggin@yahoo.com.au, wenji@fnal.gov, akpm@osdl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [patch 1/4] - Potential performance bottleneck for Linxu TCP Message-ID: <20061130205428.GA21140@elte.hu> References: <20061130103240.GA25733@elte.hu> <20061130.122258.68041055.davem@davemloft.net> <20061130203026.GD14696@elte.hu> <20061130.123853.10298783.davem@davemloft.net> <20061130204908.GA19393@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20061130204908.GA19393@elte.hu> User-Agent: Mutt/1.4.2.2i X-ELTE-VirusStatus: clean X-ELTE-SpamScore: 0.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.0 required=5.9 tests=none autolearn=no SpamAssassin version=3.0.3 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1039 Lines: 22 * Ingo Molnar wrote: > [...] Instead what i'd like to see is more TCP performance (and a > nicer over-the-wire behavior - no retransmits for example) /with the > same 10% CPU time used/. Are we in rough agreement? put in another way: i'd like to see the "TCP bytes transferred per CPU time spent by the TCP stack" ratio to be maximized in a load-independent way (part of which is the sender host too: to not cause unnecessary retransmits is important as well). In a high-load scenario this means that any measure that purely improves TCP throughput by giving it more cycles is not a real improvement. So the focus should be on throttling intelligently and without causing extra work on the sender side either - not on trying to circumvent throttling measures. Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/