Re: OOM notifications

Martin Bligh
2007-10-26T21:59:16Z

Rik van Riel wrote:
> On Fri, 26 Oct 2007 14:11:12 -0700
> Andrew Morton <akpm@linux-foundation.org> wrote:
>
>> Sure, but in terms of high-level userspace interface, being able to
>> select() on a group of priority buckets (spread across different
>> nodes, zones and cgroups) seems a lot more flexible than any
>> signal-based approach we could come up with.
>
> Absolutely, the process needs to be able to just poll or
> select on a file descriptor from the process main loop.
>
> I am not convinced that the magic of NUMA memory distribution
> and NUMA memory pressure should be visible to userspace. Due
> to the thundering herd problem we cannot wake up all of the
> processes that select on the filedescriptor at the same time
> anyway, so we can (later on) add NUMA magic to the process
> selection logic in the kernel to only wake up processes on
> the right NUMA nodes.
>
> The initial patch probably does not need that.

Depends if you're using cpusets or not, I think?