Re: [PATCH 1/5] cpuset memory spread basic implementation

[Christoph Lameter]

On Tue, 7 Feb 2006, Ingo Molnar wrote:

> * Andi Kleen <ak@xxxxxxx> wrote:
> 
> > I still don't really think it will make much difference if the file 
> > cache is local or global. Compare to disk IO it is still infinitely 
> > faster, so a relatively small slowdown from going off node is not that 
> > big an issue.
> 
> well, maybe the SGI folks can give us some numbers?

The latency may grow (average) by a factor of 4 (same thoughput though on 
our boxes). On some architectures it is significantly more and also the 
bandwidth is reduced.

This is a significant factor. Applications that do not manage locality 
correctly loose at least 30-40% performance.

-
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/