linux-kernel - Re: [patch 0/7] cpuset writeback throttling

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: <20081104143534.b5c16147.akpm@linux-foundation.org>
Date:	Tue, 4 Nov 2008 14:35:34 -0800
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	Christoph Lameter <cl@...ux-foundation.org>
Cc:	peterz@...radead.org, rientjes@...gle.com, npiggin@...e.de,
	menage@...gle.com, dfults@....com, linux-kernel@...r.kernel.org,
	containers@...ts.osdl.org
Subject: Re: [patch 0/7] cpuset writeback throttling

On Tue, 4 Nov 2008 16:17:52 -0600 (CST)
Christoph Lameter <cl@...ux-foundation.org> wrote:

> On Tue, 4 Nov 2008, Andrew Morton wrote:
> 
> > What are the alternatives here?  What do we need to do to make
> > throttling a per-memcg thing?
> 
> Add statistics to the memcg lru and then you need some kind of sets of 
> memcgs that are represented by bitmaps or so attached to an inode.
> 
> > The patchset is badly misnamed, btw.  It doesn't throttle writeback -
> > in fact several people are working on IO bandwidth controllers and
> > calling this thing "writeback throttling" risks confusion.
> 
> It is limiting dirty pages and throttling the dirty rate of applications 
> in a  NUMA system (same procedure as we do in non NUMA). The excessive 
> dirtying without this patchset can cause OOMs to occur on NUMA systems.

yup.

To fix this with a memcg-based throttling, the operator would need to
be able to create memcg's which have pages only from particular nodes. 
(That's a bit indirect relative to what they want to do, but is
presumably workable).

But do we even have that capability now?

--
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/