Date: Mon, 27 Jul 2009 23:27:12 -0400
From: Vivek Goyal <vgoyal@redhat.com>
To: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Cc: linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org,
       dm-devel@redhat.com, jens.axboe@oracle.com, nauman@google.com,
       dpshah@google.com, lizf@cn.fujitsu.com, mikew@google.com,
       fchecconi@gmail.com, paolo.valente@unimore.it, ryov@valinux.co.jp,
       fernando@oss.ntt.co.jp, s-uchida@ap.jp.nec.com, taka@valinux.co.jp,
       jmoyer@redhat.com, dhaval@linux.vnet.ibm.com, balbir@linux.vnet.ibm.com,
       righi.andrea@gmail.com, m-ikeda@ds.jp.nec.com, jbaron@redhat.com,
       agk@redhat.com, snitzer@redhat.com, akpm@linux-foundation.org,
       peterz@infradead.org
Subject: Re: [RFC] IO scheduler based IO controller V6
Message-ID: <20090728032712.GC3620@redhat.com>
References: <1246564917-19603-1-git-send-email-vgoyal@redhat.com> <4A6D0C9A.3080600@cn.fujitsu.com> <20090727125503.GA24449@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20090727125503.GA24449@redhat.com>
User-Agent: Mutt/1.5.18 (2008-05-17)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 3034
Lines: 102

On Mon, Jul 27, 2009 at 08:55:03AM -0400, Vivek Goyal wrote:
> On Mon, Jul 27, 2009 at 10:10:34AM +0800, Gui Jianfeng wrote:
> > Hi，
> > 
> > Here are some fio test results for IO Controller V6 built and not built.
> > Iozone test results are also attached.
> > 
> 
> Hi Gui,
> 
> Thanks a lot for some performance numbers. It seems to be a mixed chart.
> Performance gains at some places and loss at others. I am curious about
> that -7.0% for normal writes. Not sure what can contribute to that.
> 

Gui, can you also try with CONFIG_TRACK_ASYNC_CONTEXT=n and see if it improves
buffered write performance.

Thanks
Vivek

> What was the value of "fairness" parameter when you ran those tests? Can you
> please set fairness = 0 and re-run the tests (if you have already not done so).
> 
> By default fairness is set to 1 in V6. With fairness = 0, we should be very
> close to existing CFQ behavior. If not, then we need to dive deeper and
> see why variations are happening.
> 
> Is it also possible to run the same tests with V7. 
> 
> Thanks
> Vivek
> 
> > Arch: X86
> > Mem:  1G
> > Disk: 320G
> > IO Scheduler: CFQ
> > 
> > ============
> > By normal read and write syscall.
> > 
> > Block Size:32K
> > File Size: 1G * 10
> > 
> > Mode                    Normal read   |   Random read   |   Normal write   |   Random write | Direct read | Direct write
> > 
> > 2.6.31-rc1              47,932KiB/s       3,566KiB/s        45,693KiB/s        8,501KiB/s     50,088KiB/s   43,473KiB/s
> > 
> > 2.6.31-rc1-Vivek-V6     47,231KiB/s       3,411KiB/s        42,451KiB/s        8,714KiB/s     51,284KiB/s   42,341KiB/s
> > 
> > Performance             -1.5%             -4.4%             -7.0%              +2.5%          +2.4%         -2.6%
> > 
> > ============
> > 
> > By mmap.
> > 
> > Block Size:32K
> > File Size: 500M
> > 
> > Mode                    Normal read   |   Random read   |   Normal write   |   Random write
> > 
> > 2.6.31-rc1              49,951KiB/s       3,245KiB/s        21,950KiB/s        2,771KiB/s
> > 
> > 2.6.31-rc1-Vivek-V6     49,951KiB/s       3,154KiB/s        22,593KiB/s        2,648KiB/s
> > 
> > Performance             0%                -2.8%             +2.9%              -4.4%
> > 
> > ============
> >  
> > By libaio calls
> > 
> > Block Size:32K
> > File Size: 500M
> > 
> > Mode                    Normal read   |  Random read   |   Normal write   |   Random write
> > 
> > 2.6.31-rc1              49,447KiB/s       3,296KiB/s        57,519KiB/s        21,093KiB/s
> > 
> > 2.6.31-rc1-Vivek-V6     50,142KiB/s       3,238KiB/s        57,791KiB/s        21,283KiB/s
> > 
> > Performance             +1.4%             -1.8%             0%                 +0.1%
> > 
> > ============
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> 
> 
> 
--
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/