Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261402AbVCKTbq (ORCPT ); Fri, 11 Mar 2005 14:31:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261380AbVCKTbK (ORCPT ); Fri, 11 Mar 2005 14:31:10 -0500 Received: from www.rapidforum.com ([80.237.244.2]:9895 "HELO rapidforum.com") by vger.kernel.org with SMTP id S261378AbVCKT1c (ORCPT ); Fri, 11 Mar 2005 14:27:32 -0500 Message-ID: <4231F112.60403@rapidforum.com> Date: Fri, 11 Mar 2005 20:27:14 +0100 From: Christian Schmid User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8a3) Gecko/20040817 X-Accept-Language: de, en MIME-Version: 1.0 To: Ben Greear CC: Andrew Morton , nickpiggin@yahoo.com.au, linux-kernel@vger.kernel.org Subject: Re: BUG: Slowdown on 3000 socket-machines tracked down References: <4229E805.3050105@rapidforum.com> <422BAAC6.6040705@candelatech.com> <422BB548.1020906@rapidforum.com> <422BC303.9060907@candelatech.com> <422BE33D.5080904@yahoo.com.au> <422C1D57.9040708@candelatech.com> <422C1EC0.8050106@yahoo.com.au> <422D468C.7060900@candelatech.com> <422DD5A3.7060202@rapidforum.com> <422F8A8A.8010606@candelatech.com> <422F8C58.4000809@rapidforum.com> <422F9259.2010003@candelatech.com> <422F93CE.3060403@rapidforum.com> <20050309211730.24b4fc93.akpm@osdl.org> <4231B95B.6020209@rapidforum.com> <4231ED18.2050804@candelatech.com> In-Reply-To: <4231ED18.2050804@candelatech.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1316 Lines: 32 Ben Greear wrote: > Christian Schmid wrote: > >> OHGAWD I GOT IT!!!!!!!! >> >> I admit, totally coincidentially but its really FIXED. Today I went to >> the puter scanning the servers by routine and wondered why the >> bandwidth is at 100% without any holes. >> >> The only thing I have done is I switched off hyper-threading because >> the server is at only 20% CPU anyway so I just disabled it. >> >> So its something with linux dealing with hyper-threading. YAY :) > > > For what it's worth, I was running dual-xeon systems with HT turned on. > > But, I have a single process, single-threaded application, so there is > not much > scheduling to be done. If you have a large number of threads or processes, > then it would make more sense for turning off HT to have an affect. This effect appeared on 1 task and on 200 tasks. I dont know what it is, but with HT off it doesnt appear anymore. The slow-down still appears when lower_zone_protection is set to 0 but the peak at 80 MB disappeared when set to 1024. I am now running at 95 MB/Sec smoothly. Chris - 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/