Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751192AbWIRVSF (ORCPT ); Mon, 18 Sep 2006 17:18:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751197AbWIRVSE (ORCPT ); Mon, 18 Sep 2006 17:18:04 -0400 Received: from tentacle.snto-msu.net ([194.88.210.4]:45718 "EHLO tentacle.sectorb.msk.ru") by vger.kernel.org with ESMTP id S1751192AbWIRVSC (ORCPT ); Mon, 18 Sep 2006 17:18:02 -0400 Date: Tue, 19 Sep 2006 01:18:00 +0400 From: "Vladimir B. Savkin" To: Andi Kleen Cc: Alexey Kuznetsov , Jesper Dangaard Brouer , Harry Edmon , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Andi Kleen Subject: Re: Network performance degradation from 2.6.11.12 to 2.6.16.20 Message-ID: <20060918211759.GB31746@tentacle.sectorb.msk.ru> References: <4492D5D3.4000303@atmos.washington.edu> <200609181754.37623.ak@suse.de> <20060918162847.GA4863@ms2.inr.ac.ru> <200609181850.22851.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline In-Reply-To: <200609181850.22851.ak@suse.de> X-Organization: Moscow State Univ., Institute of Mechanics X-Operating-System: Linux 2.6.17-rc6-64 User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1050 Lines: 25 On Mon, Sep 18, 2006 at 06:50:22PM +0200, Andi Kleen wrote: > > I suppose in the worst case a sysctl like Vladimir asked for could be added, > but it would seem somewhat lame. > Please think about it this way: suppose you haave a heavily loaded router and some network problem is to be diagnosed. You run tcpdump and suddenly router becomes overloaded (by switching to timestamp-it-all mode), drops OSPF adjancecies etc. Users are angry, and you can't diagnose anything. But with impresise timestamps and maybe even with reordered packets you still have some traces to analyze. So, in this particular corner case it's not that lame. Or maybe patching tcpdump will do better? ~ :wq With best regards, Vladimir Savkin. - 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/