linux-kernel - Re: IO scheduler based IO Controller V2

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20090507.091858.226775723.ryov@valinux.co.jp>
Date:	Thu, 07 May 2009 09:18:58 +0900 (JST)
From:	Ryo Tsuruta <ryov@...inux.co.jp>
To:	vgoyal@...hat.com
Cc:	akpm@...ux-foundation.org, nauman@...gle.com, dpshah@...gle.com,
	lizf@...fujitsu.com, mikew@...gle.com, fchecconi@...il.com,
	paolo.valente@...more.it, jens.axboe@...cle.com,
	fernando@....ntt.co.jp, s-uchida@...jp.nec.com, taka@...inux.co.jp,
	guijianfeng@...fujitsu.com, jmoyer@...hat.com,
	dhaval@...ux.vnet.ibm.com, balbir@...ux.vnet.ibm.com,
	linux-kernel@...r.kernel.org,
	containers@...ts.linux-foundation.org, righi.andrea@...il.com,
	agk@...hat.com, dm-devel@...hat.com, snitzer@...hat.com,
	m-ikeda@...jp.nec.com, peterz@...radead.org
Subject: Re: IO scheduler based IO Controller V2

Hi Vivek,

> Ryo, dm-ioband breaks the notion of classes and priority of CFQ because
> of FIFO dispatch of buffered bios. Apart from that it tries to provide
> fairness in terms of actual IO done and that would mean a seeky workload
> will can use disk for much longer to get equivalent IO done and slow down
> other applications. Implementing IO controller at IO scheduler level gives
> us tigher control. Will it not meet your requirements? If you got specific
> concerns with IO scheduler based contol patches, please highlight these and
> we will see how these can be addressed.

I'd like to avoid making complicated existing IO schedulers and other
kernel codes and to give a choice to users whether or not to use it.
I know that you chose an approach that using compile time options to
get the same behavior as old system, but device-mapper drivers can be
added, removed and replaced while system is running.

Thanks,
Ryo Tsuruta
--
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/