Re: [RFC] [PATCH] Cgroup based OOM killer controller

David Rientjes
2009-01-27T09:38:53Z

On Tue, 27 Jan 2009, Evgeniy Polyakov wrote:

> /dev/mem_notify is a great idea, but please do not limit existing
> oom-killer in its ability to do the job and do not rely on application's
> ability to send a SIGKILL which will not kill tasks in unkillable state
> contrary to oom-killer.
>

You're missing the point, /dev/mem_notify would notify userspace of lowmem
situations and allow it to respond appropriately in any number of ways
before an oom condition exists.

When the system (or cpuset, memory controller, etc) is oom, userspace can
choose to defer to the oom killer so that it may kill a task that would
most likely lead to future memory freeing with access to memory reserves.

There is no additional oom killer limitation imposed here, nor can the oom
killer kill a task hung in D state any better than userspace.

Thanks.