Re: [rfc][patch 1/3] slub: fix small HWCACHE_ALIGN alignment

Christoph Lameter
2008-03-07T02:21:20Z

On Fri, 7 Mar 2008, Nick Piggin wrote:

> > Do you have a case in mind where that would be useful? We had a
>
> Patch 3/3

Those already have SLAB_HWCACHE_ALIGN.

The point is to switch off alignment for UP? Cant we do that with
SLAB_HWCACHE_ALIGN too since SLOB seemed to work successfully without it
in the past?

> > Note that there is also KMEM_CACHE which picks up the alignment from
> > the compiler.
>
> Yeah, that's not quite as good either. My allocation flag is dynamic, so
> it will not bloat things for no reason on UP machines and SMP kernels.
> It also aligns to the detected machine cacheline size rather than a
> compile time constant.

Is that really a noteworthy effect?