Re: [PATCH] Documentation/memcg: update memcg/kmem status

Jonathan Corbet
2015-04-04T13:29:42Z

On Wed, 1 Apr 2015 18:17:17 +0300
Vladimir Davydov <vdavydov@parallels.com> wrote:

> > So the text you've removed says not to select kmem support "unless for
> > development purposes." Do we now believe that this feature is ready for
> > use in a production setting? If the answer is "yes," I'd be happy to
> > take this through the docs tree.
>
> I added this warning because of the following issues, which made
> memcg/kmem useless:
>
> - no reclaim support
> - lack of memcg slab caches auto destruction
> - several obvious races/bugs
>
> They are all fixed now, so I think the answer is yes, it can be used in
> production. There might be bugs that I am not aware of, of course, but
> It must be safe to compile it in anyway, because memcg/kmem accounting
> is disabled by default and must be enabled explicitly at runtime by
> writing to cgroup/memory.kmem.limit_in_bytes.

So I believe you, but I'm still a bit nervous about taking this one
because I can't really judge whether we should be advising people to turn
on this feature at this point or not. A well-placed ack or two would
help there; otherwise, Andrew, if you think it makes sense, you can just
grab it :)