[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <49E84BF5.4070604@cn.fujitsu.com>
Date: Fri, 17 Apr 2009 17:29:25 +0800
From: Gui Jianfeng <guijianfeng@...fujitsu.com>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
CC: Andrea Righi <righi.andrea@...il.com>,
Paul Menage <menage@...gle.com>,
Balbir Singh <balbir@...ux.vnet.ibm.com>, agk@...rceware.org,
akpm@...ux-foundation.org, axboe@...nel.dk, baramsori72@...il.com,
Carl Henrik Lunde <chlunde@...g.uio.no>,
dave@...ux.vnet.ibm.com, Divyesh Shah <dpshah@...gle.com>,
eric.rannaud@...il.com, fernando@....ntt.co.jp,
Hirokazu Takahashi <taka@...inux.co.jp>,
Li Zefan <lizf@...fujitsu.com>, matt@...ehost.com,
dradford@...ehost.com, ngupta@...gle.com, randy.dunlap@...cle.com,
roberto@...it.it, Ryo Tsuruta <ryov@...inux.co.jp>,
Satoshi UCHIDA <s-uchida@...jp.nec.com>,
subrata@...ux.vnet.ibm.com, yoshikawa.takuya@....ntt.co.jp,
containers@...ts.linux-foundation.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/9] io-throttle documentation
KAMEZAWA Hiroyuki wrote:
> On Fri, 17 Apr 2009 15:34:53 +0800
> Gui Jianfeng <guijianfeng@...fujitsu.com> wrote:
>
>> KAMEZAWA Hiroyuki wrote:
>>> On Tue, 14 Apr 2009 22:21:12 +0200
>>> Andrea Righi <righi.andrea@...il.com> wrote:
>>>
>>>> +Example:
>>>> +* Create an association between an io-throttle group and a bio-cgroup group
>>>> + with "bio" and "blockio" subsystems mounted in different mount points:
>>>> + # mount -t cgroup -o bio bio-cgroup /mnt/bio-cgroup/
>>>> + # cd /mnt/bio-cgroup/
>>>> + # mkdir bio-grp
>>>> + # cat bio-grp/bio.id
>>>> + 1
>>>> + # mount -t cgroup -o blockio blockio /mnt/io-throttle
>>>> + # cd /mnt/io-throttle
>>>> + # mkdir foo
>>>> + # echo 1 > foo/blockio.bio_id
>>> Why do we need multiple cgroups at once to track I/O ?
>>> Seems complicated to me.
>> Hi Kamezawa-san,
>>
>> The original thought to implement this function is for sharing a bio-cgroup
>> with other subsystems, such as dm-ioband. If the bio-cgroup is already mounted,
>> and used by dm-ioband or others, we just need to create a association between
>> io-throttle and bio-cgroup by echo a bio-cgroup id, just like what dm-ioband does.
>>
>
> - Why we need multiple I/O controller ?
> - Why bio-cgroup cannot be a _pure_ infrastructe as page_cgroup ?
> - Why we need extra mount ?
>
> I have no answer but, IMHO,
> - only one I/O controller should be enabled at once.
> - bio cgroup should be tightly coupled with I/O controller and should work as
> infrastructure i.e. naming/tagging I/O should be automatically done by
> I/O controller. not by the user's hand.
It seems dm-ioband has to make use of bio-cgroup by the user's hand. Because dm-ioband
is not cgroup based. :(
Is that possible that another subsystem(not cgroup based, and not an IO Controller) also
would like to use bio-cgroup in the future? There's no such case at least now, so i don't
object to get rid of this part. :)
>
> Thanks,
> -Kame
>
>
>
>
>
--
Regards
Gui Jianfeng
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists