[RFC] oom, memcg: handle sysctl oom_kill_allocating_task while memcg oom happening

[Marian Marinov <mm@1h.com>]

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Hello,
a while back in 2012 there was a request for this functionality.
  oom, memcg: handle sysctl oom_kill_allocating_task while memcg oom happening

This is the thread:  https://lkml.org/lkml/2012/10/16/168

Now we run a several machines with around 10k processes on each machine, using containers.

Regularly we see OOM from within a container that causes performance degradation.

We are running 3.12.20 with the following OOM configuration and memcg oom enabled:

vm.oom_dump_tasks = 0
vm.oom_kill_allocating_task = 1
vm.panic_on_oom = 0

When OOM occurs we see very high numbers for the loadavg and the overall responsiveness of the machine degrades.

During these OOM states the load of the machine gradualy increases from 25 up to 120 in the interval of 10minutes.

Once we manually bring down the memory usage of a container(killing some tasks) the load drops down to 25 within 5 to
7 minutes.

I read the whole thread from 2012 but I do not see the expected behavior that is described by the people that
commented the issue.

In this case, with real usage for this patch, would it be considered for inclusion?

Marian


- -- 
Marian Marinov
Founder & CEO of 1H Ltd.
Jabber/GTalk: hackman@jabber.org
ICQ: 7556201
Mobile: +359 886 660 270
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