[Devel] Re: [PATCH v3 06/16] memcg: infrastructure to match an allocation to the right cache

[Christoph Lameter]

On Tue, 25 Sep 2012, Glauber Costa wrote:

> >> 1) Do like the events mechanism and allocate this in a separate
> >> structure. Add a pointer chase in the access, and I don't think it helps
> >> much because it gets allocated anyway. But we could at least
> >> defer it to the time when we limit the cache.
> >
> > Start at some reasonable size and then double it as usage grows?  How
> > many kmem_caches do we typically end up using?
> >
>
> So my Fedora box here, recently booted on a Fedora kernel, will have 111
> caches. How would 150 sound to you?

Some drivers/subsystems can dynamically create slabs as needed for new
devices or instances of metadata. You cannot use a fixed size
array and cannot establish an upper boundary for the number of slabs on
the system.