linux-kernel - Re: [PATCH] cgroup: limit block I/O bandwidth

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]

Date:	Sun, 20 Jan 2008 16:41:54 +0100 (MET)
From:	Andrea Righi <righiandr@...rs.sourceforge.net>
To:	Jens Axboe <jens.axboe@...cle.com>
Cc:	Naveen Gupta <ngupta@...gle.com>, Paul Menage <menage@...gle.com>,
	Dhaval Giani <dhaval@...ux.vnet.ibm.com>,
	Balbir Singh <balbir@...ux.vnet.ibm.com>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] cgroup: limit block I/O bandwidth

Jens Axboe wrote:
> Your approach is totally flawed, imho. For instance, you don't want a
> process to be able to dirty memory at foo mb/sec but only actually
> write them out at bar mb/sec.

Right. Actually my problem here is that the processes that write out
blocks are different respect to the processes that write bytes in
memory, and I would be able to add limits on those processes that are
dirtying memory.

> The noop-iosched changes are also very buggy. The queue back pointer
> breaks reference counting and the task pointer storage assumes the task
> will also always be around. That's of course not the case.

Yes, this really need a lot of fixes. I simply posted the patch to know
if such approach (in general) could have sense or not.

> IOW, you are doing this at the wrong level.
> 
> What problem are you trying to solve?

Limiting block I/O bandwidth for tasks that belong to a generic cgroup,
in order to provide a sort of a QoS on block I/O.

Anyway, I'm quite new in the wonderful land of the I/O scheduling, so
any help is appreciated.

Thanks,
-Andrea
--
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/