Re: [POLL] SLAB : Are the 32 and 192 bytes caches really usefull on x86_64 machines ?

[Andi Kleen]

On Monday 02 January 2006 09:37, Pekka Enberg wrote:
> On 12/28/05, Andreas Kleen <ak@xxxxxxx> wrote:
> > I remember the original slab paper from Bonwick actually mentioned that
> > power of two slabs are the worst choice for a malloc - but for some reason Linux
> > chose them anyways.
> 
> Power of two sizes are bad because memory accesses tend to concentrate
> on the same cache lines but slab coloring should take care of that. So
> I don't think there's a problem with using power of twos for kmalloc()
> caches.

There is - who tells you it's the best possible distribution of memory? 

-Andi


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