From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270792AbTGNUXW (ORCPT ); Mon, 14 Jul 2003 16:23:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270765AbTGNUNo (ORCPT ); Mon, 14 Jul 2003 16:13:44 -0400 Received: from sea2-f51.sea2.hotmail.com ([207.68.165.51]:15624 "EHLO hotmail.com") by vger.kernel.org with ESMTP id S270764AbTGNUI1 (ORCPT ); Mon, 14 Jul 2003 16:08:27 -0400 X-Originating-IP: [143.182.124.3] X-Originating-Email: [dagriego@hotmail.com] From: "David griego" To: jgarzik@pobox.com Cc: alan@storlinksemi.com, linux-kernel@vger.kernel.org Subject: Re: Alan Shih: "TCP IP Offloading Interface" Date: Mon, 14 Jul 2003 13:23:12 -0700 Mime-Version: 1.0 Content-Type: text/plain; format=flowed Message-ID: X-OriginalArrivalTime: 14 Jul 2003 20:23:12.0436 (UTC) FILETIME=[BF9BBF40:01C34A45] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >From: Jeff Garzik >To: David griego >CC: alan@storlinksemi.com, linux-kernel@vger.kernel.org >Subject: Re: Alan Shih: "TCP IP Offloading Interface" >Date: Mon, 14 Jul 2003 16:03:01 -0400 > >David griego wrote: >>Intel Clusters and Network Storage Volume Platforms Lab reported that it >>takes about 1MHz to process 1Mbps on a PIII. Using this rule of thumb >>(they showed it scaling from 400MHz to 800MHz) it would take 10GHz to >>process 10Mbps. Well you might say "what about multi-processers?" This > >Um. It doesn't take nearly 10Ghz to handle 10Mbps, or even 100Mbps. Err. Make that 10GHz for 10Gbps :-) > > >>would be good for people that have multi-processors, but there is a large >>segment of embedded processors that are not going have SMP, or be at 10GHz >>anytime soon. Besides that processing interrupts does not scale across >>MPs liniarly. The truth is that communication speeds are outpacing >>processor speeds at this time. > >If the host CPU is a bottleneck after large-send and checksums have been >offloaded, then logically you aren't getting any work done _anyway_. You >have to interface with the net stack at some point, in which case you incur >a fixed cost, for socket handling, TCP exception handling, etc. Still other processing going on like RAID, NFS, or CIFS. > >Maybe somebody needs to be looking into AMP (asymmetric multiprocessing), >too. Nice artical on AMP for ATM. I'll try to find a pointer. > > Jeff > > > _________________________________________________________________ MSN 8 with e-mail virus protection service: 2 months FREE* http://join.msn.com/?page=features/virus