Re: [patches] [PATCH] [8/35] x86_64: a memcpy that tries to reducecache pressure

From: Andi Kleen
Date: Mon Apr 30 2007 - 05:10:30 EST


On Monday 30 April 2007 09:26:05 Jan Beulich wrote:
> >+ testb $8, %dxl /* rdx is 3,5,6,7,9..15 */
>
> Could you use the more conventional name %dl (or whatever is being meant)
> here?
>
> >+.L42:
> >+ prefetchnta 128(%rsi)
>
> I think I commented similarly on a previous version of the patch: This will
> - result in still bringing the first 128 bytes into the cache
> - prevent caching of memory beyond the buffer being dealt with

Yes I remember, somehow it got lost. I agree it's a bad thing. Will drop
the patch for now especially since nothing seems to really need it right now.

Thanks,

-Andi
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