From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1754198Ab1HCErl (ORCPT <rfc822;w@1wt.eu>);
	Wed, 3 Aug 2011 00:47:41 -0400
Received: from cn.fujitsu.com ([222.73.24.84]:56196 "EHLO song.cn.fujitsu.com"
	rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP
	id S1753999Ab1HCEre (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Wed, 3 Aug 2011 00:47:34 -0400
Message-ID: <4E38D2F5.5050702@cn.fujitsu.com>
Date: Wed, 03 Aug 2011 12:47:49 +0800
From: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:5.0) Gecko/20110624 Thunderbird/5.0
MIME-Version: 1.0
To: Dave Chinner <david@fromorbit.com>
CC: Vivek Goyal <vgoyal@redhat.com>, Jens Axboe <jaxboe@fusionio.com>,
        linux-kernel@vger.kernel.org
Subject: Re: fio posixaio performance problem
References: <4E38C314.8070305@cn.fujitsu.com> <20110803040613.GJ12870@dastard>
In-Reply-To: <20110803040613.GJ12870@dastard>
X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at
 2011-08-03 12:46:29,
	Serialize by Router on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at
 2011-08-03 12:46:31,
	Serialize complete at 2011-08-03 12:46:31
Content-Transfer-Encoding: 7bit
Content-Type: text/plain; charset=ISO-8859-1
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 2011-8-3 12:06, Dave Chinner wrote:
> On Wed, Aug 03, 2011 at 11:40:04AM +0800, Gui Jianfeng wrote:
>> Hi,
>>
>> I ran a fio test to simulate qemu-kvm io behaviour.
>> When job number is greater than 2, IO performance is
>> really bad.
>>
>> 1 thread: aggrb=15,129KB/s
>> 4 thread: aggrb=1,049KB/s
>>
>> Kernel: lastest upstream
>>
>> Any idea?
>>
>> ---
>> [global]
>> runtime=30
>> time_based=1
>> size=1G
>> group_reporting=1
>> ioengine=posixaio
>> exec_prerun='echo 3 > /proc/sys/vm/drop_caches'
>> thread=1
>>
>> [kvmio-1]
>> description=kvmio-1
>> numjobs=4
>> rw=write
>> bs=4k
>> direct=1
>> filename=/mnt/sda4/1G.img
> 
> What filesystem?

Ext4

Thanks,
Gui

> 
> Cheers,
> 
> Dave.