Re: [PATCH] zerocopy NFS for 2.5.36

Alan Cox (
19 Sep 2002 11:42:43 +0100

On Thu, 2002-09-19 at 04:30, Andrew Morton wrote:
> > It's disappointing that this program doesn't seem to support
> > benchmarking of MMX copy loops (like the ones in arch/i386/lib/mmx.c).
> > Those seem to be the more interesting memcpy functions on modern
> > systems.
> Well the source is there, and the licensing terms are most reasonable.
> But then, the source was there eighteen months ago and nothing happened.
> Sigh.
> I think in-kernel MMX has fatal drawbacks anyway. Not sure what
> they are - I prefer to pretend that x86 CPUs execute raw C.

MMX isnt useful for anything smaller than about 512bytes-1K. Its not
useful in interrupt handlers. The list goes on.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at