linux-kernel - Re: [PATCH 3/3] mm: memcontrol: fix cgroup creation failure after many small jobs

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:	Fri, 17 Jun 2016 14:18:42 -0400
From:	Tejun Heo <tj@...nel.org>
To:	Johannes Weiner <hannes@...xchg.org>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Vladimir Davydov <vdavydov@...tuozzo.com>,
	Michal Hocko <mhocko@...e.cz>, Li Zefan <lizefan@...wei.com>,
	linux-mm@...ck.org, cgroups@...r.kernel.org,
	linux-kernel@...r.kernel.org, kernel-team@...com
Subject: Re: [PATCH 3/3] mm: memcontrol: fix cgroup creation failure after
 many small jobs

On Fri, Jun 17, 2016 at 12:25:16PM -0400, Johannes Weiner wrote:
> The memory controller has quite a bit of state that usually outlives
> the cgroup and pins its CSS until said state disappears. At the same
> time it imposes a 16-bit limit on the CSS ID space to economically
> store IDs in the wild. Consequently, when we use cgroups to contain
> frequent but small and short-lived jobs that leave behind some page
> cache, we quickly run into the 64k limitations of outstanding CSSs.
> Creating a new cgroup fails with -ENOSPC while there are only a few,
> or even no user-visible cgroups in existence.

Acked-by: Tejun Heo <tj@...nel.org>

Thanks.

-- 
tejun