Re: [PATCH] mm-slab: allocate kmem_cache with __GFP_REPEAT

[Christoph Lameter]

On Wed, 20 Jul 2011, Eric Dumazet wrote:

> Note that adding ____cacheline_aligned_in_smp on nodelists[] actually
> helps performance, as all following fields are readonly after kmem_cache
> setup.

Well but that is not addresssing the same issue. Could you separate that
out?

The other question that follows from this is then: Does that
alignment compensate for the loss of performance due to the additional
lookup in hot code paths and the additional cacheline reference required?

The per node pointers are lower priority in terms of performance than the
per cpu pointers. I'd rather have the per node pointers requiring an
additional lookup. Less impact on hot code paths.

--
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/