linux-kernel - Re: [PATCH mm v5 0/9] memcg: accounting for objects allocated by mkdir, cgroup

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, 24 Jun 2022 14:26:10 +0200
From:   Michal Koutný <mkoutny@...e.com>
To:     Vasily Averin <vvs@...nvz.org>
Cc:     Shakeel Butt <shakeelb@...gle.com>, Michal Hocko <mhocko@...e.com>,
        kernel@...nvz.org, Andrew Morton <akpm@...ux-foundation.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Linux MM <linux-mm@...ck.org>,
        Roman Gushchin <roman.gushchin@...ux.dev>,
        Vlastimil Babka <vbabka@...e.cz>,
        Muchun Song <songmuchun@...edance.com>,
        Cgroups <cgroups@...r.kernel.org>
Subject: Re: [PATCH mm v5 0/9] memcg: accounting for objects allocated by
 mkdir, cgroup

On Fri, Jun 24, 2022 at 01:40:14PM +0300, Vasily Averin <vvs@...nvz.org> wrote:
> Btw could you please explain why memory cgroups have MEM_CGROUP_ID_MAX limit
> Why it is required at all and why it was set to USHRT_MAX? I believe that
> in the future it may be really reachable:

IIRC, one reason is 2B * nr_swap_pages of memory overhead (in
swap_cgroup_swapon()) that's ~0.05% of swap space occupied additionally
in RAM (fortunately swap needn't cover whole RAM).

HTH,
Michal

Download attachment "signature.asc" of type "application/pgp-signature" (229 bytes)