Re: [RFC PATCH] mm, oom: introduce vm.sacrifice_hugepage_on_oom

From: Michal Hocko
Date: Wed Feb 17 2021 - 07:41:52 EST


On Wed 17-02-21 13:31:07, Michal Hocko wrote:
[...]
> Thanks for your usecase description. It helped me to understand what you
> are doing and how this can be really useful for your particular setup.
> This is really a very specific situation from my POV. I am not yet sure
> this is generic enough to warrant for a yet another tunable. One thing
> you can do [1] is to
> hook into oom notifiers interface (register_oom_notifier) and release
> pages from the callback.

Forgot to mention that this would be done from a kernel module.

> Why is that batter than a global tunable?
> For one thing you can make the implementation tailored to your specific
> usecase. As the review feedback has shown this would be more tricky to
> be done in a general case. Unlike a generic solution it would allow you
> to coordinate with your userspace if you need. Would something like that
> work for you?
>
> ---
> [1] and I have to say I hate myself for suggesting that because I was
> really hoping this interface would go away. But the reality disagrees so
> I gave up on that goal...
> --
> Michal Hocko
> SUSE Labs

--
Michal Hocko
SUSE Labs