From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [patch 1/4] - Potential performance bottleneck for Linxu TCP Date: Thu, 30 Nov 2006 12:38:53 -0800 (PST) Message-ID: <20061130.123853.10298783.davem@davemloft.net> References: <20061130103240.GA25733@elte.hu> <20061130.122258.68041055.davem@davemloft.net> <20061130203026.GD14696@elte.hu> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: johnpol@2ka.mipt.ru, nickpiggin@yahoo.com.au, wenji@fnal.gov, akpm@osdl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:60884 "EHLO sunset.davemloft.net") by vger.kernel.org with ESMTP id S1031407AbWK3Uiv (ORCPT ); Thu, 30 Nov 2006 15:38:51 -0500 To: mingo@elte.hu In-Reply-To: <20061130203026.GD14696@elte.hu> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Ingo Molnar Date: Thu, 30 Nov 2006 21:30:26 +0100 > disk I/O is typically not CPU bound, and i believe these TCP tests /are/ > CPU-bound. Otherwise there would be no expiry of the timeslice to begin > with and the TCP receiver task would always be boosted to 'interactive' > status by the scheduler and would happily chug along at 500 mbits ... It's about the prioritization of the work. If all disk I/O were shut off and frozen while we copy file data into userspace, you'd see the same problem for disk I/O.