linux-kernel - Re: [PATCH] mm-slab: allocate kmem_cache with __GFP

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: <20110720190933.GN5349@suse.de>
Date:	Wed, 20 Jul 2011 20:09:33 +0100
From:	Mel Gorman <mgorman@...e.de>
To:	Pekka Enberg <penberg@...nel.org>
Cc:	Christoph Lameter <cl@...ux.com>,
	Eric Dumazet <eric.dumazet@...il.com>,
	Konstantin Khlebnikov <khlebnikov@...nvz.org>,
	Andrew Morton <akpm@...ux-foundation.org>, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org, Matt Mackall <mpm@...enic.com>
Subject: Re: [PATCH] mm-slab: allocate kmem_cache with __GFP_REPEAT

On Wed, Jul 20, 2011 at 08:41:12PM +0300, Pekka Enberg wrote:
> On Wed, 20 Jul 2011, Pekka Enberg wrote:
> >>On Wed, 20 Jul 2011, Eric Dumazet wrote:
> >>>>[PATCH v2] slab: shrinks sizeof(struct kmem_cache)
> >>
> >>On Wed, 20 Jul 2011, Christoph Lameter wrote:
> >>>This will solve the issue for small nr_cpu_ids but those with 4k cpus will
> >>>still have the issue.
> >>>
> >>>Acked-by: Christoph Lameter <cl@...ux.com>
> >>
> >>Applied, thanks! Do we still want the __GFP_REPEAT patch from Konstantin
> >>though?
> 
> On Wed, 20 Jul 2011, Christoph Lameter wrote:
> >Those with 4k cpus will be thankful I guess.
> 
> OTOH, I'm slightly worried that it might mask a real problem with
> GFP_KERNEL not being aggressive enough. Mel?
> 

The reproduction case was while memory was under heavy pressure
(swapout was active) and even then only 1 in a 1000 containers were
failing to create due to an order-4 allocation failure. I'm not
convinced we need to increase how aggressive the allocator is for
PAGE_ALLOC_COSTLY_ORDER in general based on this.

-- 
Mel Gorman
SUSE Labs
--
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/