From: Michal Hocko <mhocko@kernel.org>
To: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
cgroups@vger.kernel.org, Roman Gushchin <guro@fb.com>,
Johannes Weiner <hannes@cmpxchg.org>
Subject: Re: [PATCH v1 0/7] mm/memcontrol: recharge mlocked pages
Date: Wed, 4 Sep 2019 16:37:47 +0200 [thread overview]
Message-ID: <20190904143747.GA3838@dhcp22.suse.cz> (raw)
In-Reply-To: <156760509382.6560.17364256340940314860.stgit@buzz>
On Wed 04-09-19 16:53:08, Konstantin Khlebnikov wrote:
> Currently mlock keeps pages in cgroups where they were accounted.
> This way one container could affect another if they share file cache.
> Typical case is writing (downloading) file in one container and then
> locking in another. After that first container cannot get rid of cache.
> Also removed cgroup stays pinned by these mlocked pages.
>
> This patchset implements recharging pages to cgroup of mlock user.
>
> There are three cases:
> * recharging at first mlock
> * recharging at munlock to any remaining mlock
> * recharging at 'culling' in reclaimer to any existing mlock
>
> To keep things simple recharging ignores memory limit. After that memory
> usage temporary could be higher than limit but cgroup will reclaim memory
> later or trigger oom, which is valid outcome when somebody mlock too much.
I assume that this is mlock specific because the pagecache which has the
same problem is reclaimable and the problem tends to resolve itself
after some time.
Anyway, how big of a problem this really is? A lingering memcg is
certainly not nice but pages are usually not mlocked for ever. Or is
this a way to protect from an hostile actor?
> Konstantin Khlebnikov (7):
> mm/memcontrol: move locking page out of mem_cgroup_move_account
> mm/memcontrol: add mem_cgroup_recharge
> mm/mlock: add vma argument for mlock_vma_page()
> mm/mlock: recharge memory accounting to first mlock user
> mm/mlock: recharge memory accounting to second mlock user at munlock
> mm/vmscan: allow changing page memory cgroup during reclaim
> mm/mlock: recharge mlocked pages at culling by vmscan
>
>
> Documentation/admin-guide/cgroup-v1/memory.rst | 5 +
> include/linux/memcontrol.h | 9 ++
> include/linux/rmap.h | 3 -
> mm/gup.c | 2
> mm/huge_memory.c | 4 -
> mm/internal.h | 6 +
> mm/ksm.c | 2
> mm/memcontrol.c | 104 ++++++++++++++++--------
> mm/migrate.c | 2
> mm/mlock.c | 14 +++
> mm/rmap.c | 5 +
> mm/vmscan.c | 17 ++--
> 12 files changed, 121 insertions(+), 52 deletions(-)
>
> --
> Signature
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2019-09-04 14:37 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-04 13:53 [PATCH v1 0/7] mm/memcontrol: recharge mlocked pages Konstantin Khlebnikov
2019-09-04 13:53 ` [PATCH v1 1/7] mm/memcontrol: move locking page out of mem_cgroup_move_account Konstantin Khlebnikov
2019-09-04 13:53 ` [PATCH v1 2/7] mm/memcontrol: add mem_cgroup_recharge Konstantin Khlebnikov
2019-09-04 13:53 ` [PATCH v1 3/7] mm/mlock: add vma argument for mlock_vma_page() Konstantin Khlebnikov
2019-09-04 13:53 ` [PATCH v1 4/7] mm/mlock: recharge memory accounting to first mlock user Konstantin Khlebnikov
2019-09-04 13:53 ` [PATCH v1 5/7] mm/mlock: recharge memory accounting to second mlock user at munlock Konstantin Khlebnikov
2019-09-04 13:53 ` [PATCH v1 6/7] mm/vmscan: allow changing page memory cgroup during reclaim Konstantin Khlebnikov
2019-09-04 13:53 ` [PATCH v1 7/7] mm/mlock: recharge mlocked pages at culling by vmscan Konstantin Khlebnikov
2019-09-04 14:37 ` Michal Hocko [this message]
2019-09-05 7:38 ` [PATCH v1 0/7] mm/memcontrol: recharge mlocked pages Konstantin Khlebnikov
2019-09-05 23:11 ` Roman Gushchin
2019-09-04 23:13 ` Roman Gushchin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190904143747.GA3838@dhcp22.suse.cz \
--to=mhocko@kernel.org \
--cc=cgroups@vger.kernel.org \
--cc=guro@fb.com \
--cc=hannes@cmpxchg.org \
--cc=khlebnikov@yandex-team.ru \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).