Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264905AbTFQTfm (ORCPT ); Tue, 17 Jun 2003 15:35:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264906AbTFQTfm (ORCPT ); Tue, 17 Jun 2003 15:35:42 -0400 Received: from e31.co.us.ibm.com ([32.97.110.129]:43433 "EHLO e31.co.us.ibm.com") by vger.kernel.org with ESMTP id S264905AbTFQTfj (ORCPT ); Tue, 17 Jun 2003 15:35:39 -0400 Message-ID: <3EEF7030.6030303@us.ibm.com> Date: Tue, 17 Jun 2003 14:46:56 -0500 From: Janice M Girouard Organization: IBM Linux Technology Center - Network Device Drivers User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.0.2) Gecko/20030208 Netscape/7.02 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Jeff Garzik CC: "David S. Miller" , shemminger@osdl.org, Valdis.Kletnieks@vt.edu, Janice Girouard , Daniel Stekloff , Larry Kessler , linux-kernel@vger.kernel.org, netdev@oss.sgi.com, niv@us.ibm.com Subject: Re: patch for common networking error messages References: <200306170434.h5H4YZPZ003025@turing-police.cc.vt.edu> <20030617090859.0ffa0ca8.shemminger@osdl.org> <20030617.090930.102574393.davem@redhat.com> <3EEF620A.40608@pobox.com> <3EEF66AA.3000509@us.ibm.com> <3EEF6A9D.6050303@pobox.com> Content-Type: multipart/related; boundary="------------010202080205050803050900" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1470 Lines: 36 --------------010202080205050803050900 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Jeff Garzik wrote: Do you want to individually send 4000 - 16000 (or more) TX stop / start events per second to userspace? :) At some point Heisenburg defeats low latency :) How about looking at 1000 byte packet transmit example. A gigabit adapter would send 125,000 packets per second. I'm thinking that most of the time, you will have enough available buffers in the adapter that you don't start to see the adapter buffers completely fill up. Are you saying that 3.2% - 12.8% of the time in this case you're disabling the tcp/ip stack because the transmit buffers on your card are completely full? Perhaps with zero copy enabled, but the tcp/ip cpu load alone will throttle your ability to fill the adapter buffers up. What does your own experience indicate for gigabit adapter cards? I could see the buffers backing up for 10/100 cards. So that case favors your point. I'm still thinking that it's a sign someone should be buying a 2nd card and ramping up their network capability. But I can see your point. --------------010202080205050803050900-- - 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/