Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261616AbVCGBO4 (ORCPT ); Sun, 6 Mar 2005 20:14:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261622AbVCGBOT (ORCPT ); Sun, 6 Mar 2005 20:14:19 -0500 Received: from ns1.lanforge.com ([66.165.47.210]:47265 "EHLO www.lanforge.com") by vger.kernel.org with ESMTP id S261616AbVCGBNp (ORCPT ); Sun, 6 Mar 2005 20:13:45 -0500 Message-ID: <422BAAC6.6040705@candelatech.com> Date: Sun, 06 Mar 2005 17:13:42 -0800 From: Ben Greear Organization: Candela Technologies User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.7.3) Gecko/20041020 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Christian Schmid CC: linux-kernel@vger.kernel.org Subject: Re: BUG: Slowdown on 3000 socket-machines tracked down References: <4229E805.3050105@rapidforum.com> In-Reply-To: <4229E805.3050105@rapidforum.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1445 Lines: 40 Christian Schmid wrote: > Hello. > > After weeks of work, I can now give a detailed report about the bug and > when it appears: > > Attached is another traffic-image. This one is with 2.6.10 and a 3/1 > split, preemtive kernel, so all defaults. What are the units on your graph. You say "MB" several places, but do you mean Mb (ie, Mega-bit) instead? I have a tool that can also generate TCP traffic on a large number of sockets. If I can understand what you are trying to do, I may be able to reproduce the problem. My biggest machine at present has only 2GB of RAM, however...not sure if that matters or not. Are you sending traffic in only one direction, or more of a full-duplex configuration? Is each socket running the same bandwidth? What is this bandwidth? Are you setting the send & rcv buffers in the socket creation code? (To what values if so?) How many bytes are you sending with each call to write()/sendto() whatever? Is there any significant latency between your sender and receiver machine? If so, how much? What is the physical transport...GigE? 1500 MTU? Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com - 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/