linux-kernel - Re: [v7 5/5] mm, oom: cgroup v2 mount option to disable cgroup-aware OOM killer

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: <alpine.DEB.2.10.1709071502430.143767@chino.kir.corp.google.com>
Date:   Thu, 7 Sep 2017 15:03:25 -0700 (PDT)
From:   David Rientjes <rientjes@...gle.com>
To:     Christopher Lameter <cl@...ux.com>
cc:     Michal Hocko <mhocko@...nel.org>,
        Johannes Weiner <hannes@...xchg.org>,
        Roman Gushchin <guro@...com>, linux-mm@...ck.org,
        Vladimir Davydov <vdavydov.dev@...il.com>,
        Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Tejun Heo <tj@...nel.org>, kernel-team@...com,
        cgroups@...r.kernel.org, linux-doc@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [v7 5/5] mm, oom: cgroup v2 mount option to disable cgroup-aware
 OOM killer

On Thu, 7 Sep 2017, Christopher Lameter wrote:

> > I am not sure this is how things evolved actually. This is way before
> > my time so my git log interpretation might be imprecise. We do have
> > oom_badness heuristic since out_of_memory has been introduced and
> > oom_kill_allocating_task has been introduced much later because of large
> > boxes with zillions of tasks (SGI I suspect) which took too long to
> > select a victim so David has added this heuristic.
> 
> Nope. The logic was required for tasks that run out of memory when the
> restriction on the allocation did not allow the use of all of memory.
> cpuset restrictions and memory policy restrictions where the prime
> considerations at the time.
> 
> It has *nothing* to do with zillions of tasks. Its amusing that the SGI
> ghost is still haunting the discussion here. The company died a couple of
> years ago finally (ok somehow HP has an "SGI" brand now I believe). But
> there are multiple companies that have large NUMA configurations and they
> all have configurations where they want to restrict allocations of a
> process to subset of system memory. This is even more important now that
> we get new forms of memory (NVDIMM, PCI-E device memory etc). You need to
> figure out what to do with allocations that fail because the *allowed*
> memory pools are empty.
> 

We already had CONSTRAINT_CPUSET at the time, this was requested by Paul 
and acked by him in https://marc.info/?l=linux-mm&m=118306851418425.