Re: [PATCH 5/8] mm: memcontrol: account socket memory on unified hierarchy

Johannes Weiner
2015-11-06T17:45:47Z

On Fri, Nov 06, 2015 at 05:46:57PM +0100, Michal Hocko wrote:
> The basic problem was that the Delegate feature has been backported to
> our systemd package without further consideration and that has
> invalidated a lot of performance testing because some resource
> controllers have measurable effects on those benchmarks.

You're talking about a userspace bug. No amount of fragmenting and
layering and opt-in in the kernel's runtime configuration space is
going to help you if you screw up and enable it all by accident.

> > All I read here is vague inflammatory language to spread FUD.
>
> I was merely pointing out that memory controller might be enabled without
> _user_ actually even noticing because the controller wasn't enabled
> explicitly. I haven't blamed anybody for that.

Why does that have anything to do with how we design our interface?

We can't do more than present a sane interface in good faith and lobby
userspace projects if we think they misuse it.