Re: 2.6.22 -mm merge plans: slub

From: Christoph Lameter
Date: Wed May 02 2007 - 14:28:43 EST


On Wed, 2 May 2007, Hugh Dickins wrote:

> On Wed, 2 May 2007, Christoph Lameter wrote:
> >
> > But these are arch specific problems. We could use
> > ARCH_USES_SLAB_PAGE_STRUCT to disable SLUB on these platforms.
>
> As a quick hack, sure. But every ARCH_USES_SLAB_PAGE_STRUCT
> diminishes the testing SLUB will get. If the idea is that we're
> going to support both SLAB and SLUB, some arches with one, some
> with another, some with either, for more than a single release,
> then I'm back to saying SLUB is being pushed in too early.
> I can understand people wanting pluggable schedulers,
> but pluggable slab allocators?

This is a sensitive piece of the kernel as you say and we better allow the
running of two allocator for some time to make sure that it behaves in all
load situations. The design is fundamentally different so its performance
characteristics may diverge significantly and perhaps there will be corner
cases for each where they do the best job.

I have already reworked the slab API to allow for an easy implementation
of alternate slab allocators (released with 2.6.20) which only covered
SLAB and SLOB. This is continuing the cleanup work and adding a third one.


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/