Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753501Ab2FLWle (ORCPT ); Tue, 12 Jun 2012 18:41:34 -0400 Received: from tru75-7-88-161-131-83.fbx.proxad.net ([88.161.131.83]:59018 "EHLO next.fork.zz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752182Ab2FLWld (ORCPT ); Tue, 12 Jun 2012 18:41:33 -0400 Message-ID: <4FD7C595.202@free.fr> Date: Wed, 13 Jun 2012 00:41:25 +0200 From: Wallak User-Agent: Mozilla/5.0 (X11; Linux i686; rv:12.0) Gecko/20120604 Firefox/12.0 SeaMonkey/2.9.1 MIME-Version: 1.0 To: Jan Kara CC: linux-kernel@vger.kernel.org Subject: Re: File copy is very slow on linux-3.4.2 (or linux-3.3x) on a specific hardware: AMD FX-8150 + 990FX References: <1108815600.134531433.1339443818361.JavaMail.root@zimbra44-e7.priv.proxad.net> <437497008.134549481.1339444456294.JavaMail.root@zimbra44-e7.priv.proxad.net> <20120612165357.GI6021@quack.suse.cz> <4FD78CE4.4000209@free.fr> <20120612210947.GB20007@quack.suse.cz> In-Reply-To: <20120612210947.GB20007@quack.suse.cz> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3251 Lines: 94 Jan Kara wrote: > On Tue 12-06-12 20:39:32, Wallak wrote: >> Jan Kara wrote: >>> On Mon 11-06-12 21:54:16, wallak@free.fr wrote: >>>> I've a very annoying issue on recent kernel (linux-3.4.2-SMP) with my main motherboard (AMD FX-8150 + 990FX - 8 cores 4.1GHz), file copy is very slow (see below). The same kernel works flawlessly on an AMD E450 2 cores motherboard. >>>> >>>> Linux-3.2.20 works properly on this hardware. >>>> hdparm -t gives good results on both kernels. >>>> >>>> I've no idea where this bug come from. Do you have this issue on your hardware ? A patch is available ? >>>> >>>> >>>> *linux-3.4.2 >>>> dd if=../in/file_8gb.tmp of=tmp.tmp bs=1024k count=100 >>>> 100+0 records in >>>> 100+0 records out >>>> 104857600 bytes (105 MB) copied, 132.884 s, 789 kB/s >>>> >>>> >>>> *linux-3.2.20 >>>> dd if=../in/file_8gb.tmp of=tmp.tmp bs=1024k count=100 >>>> 100+0 records in >>>> 100+0 records out >>>> 104857600 bytes (105 MB) copied, 3.30793 s, 31.7 MB/s >>> So let's separate reading and writing part first. What is the speed of >>> dd if=../in/file_8gb.tmp of=/dev/null bs=1M count=100 >>> on both kernels? >>> And what is the speed of: >>> dd if=/dev/zero of=tmp.tm bs=1M count=100 >> You're right, the issue is only while writing. The results are below: >> >> #linux-3.4.2 >> dd if=/dev/zero of=tmp.tm bs=1M count=100 >> 100+0 records in >> 100+0 records out >> 104857600 bytes (105 MB) copied, 151.347 s, 693 kB/s >> dd if=../in/file_8gb.tmp of=/dev/null bs=1M count=100 >> 100+0 records in >> 100+0 records out >> 104857600 bytes (105 MB) copied, 1.26228 s, 83.1 MB/s >> >> #linux-3.2.20 >> dd if=/dev/zero of=tmp.tm bs=1M count=100 >> 100+0 records in >> 100+0 records out >> 104857600 bytes (105 MB) copied, 1.00838 s, 104 MB/s >> dd if=../in/file_8gb.tmp of=/dev/null bs=1M count=100 >> 100+0 records in >> 100+0 records out >> 104857600 bytes (105 MB) copied, 1.26947 s, 82.6 MB/s >> >> >>> Also what filesystems are you using? >> This is an ext2 file system: >> >> /dev/sda6 ext2 464463364 323380956 141082408 70% /backup > OK, I'm surprised by one thing - how come the writes do no end up cached > in memory (thus you should get much higher throughput). Is the filesystem > mounted with -o sync option by any chance? > > Honza I've tried with an nfs mounted drive, the issue is still there, it seems to be global. With sync enabled, the output is quite faster, that's quite unexpected. On my AMD E450 motherboard this kernel works fine - Are you able to reproduce this behavior ? #/dev/sda6 /backup ext2 rw,relatime,errors=continue 0 0 (/proc/mount) 100+0 records in 100+0 records out 104857600 bytes (105 MB) copied, 155.407 s, 675 kB/s #/dev/sda6 /backup ext2 rw,sync,relatime,errors=continue 0 0 100+0 records in 100+0 records out 104857600 bytes (105 MB) copied, 69.7868 s, 1.5 MB/s #nfs drive - same issue: 100+0 records in 100+0 records out 104857600 bytes (105 MB) copied, 221.572 s, 473 kB/s Best Regards, Wallak. -- 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/