Re: [PATCH] use movntq version of fast_clear_page/fast_copy_page on Geode

From: Marcelo Tosatti
Date: Thu Feb 15 2007 - 10:05:00 EST


On Wed, Feb 14, 2007 at 09:16:46PM +0000, Alan wrote:
> On Wed, 14 Feb 2007 17:08:39 -0200
> Marcelo Tosatti <marcelo@xxxxxxxxx> wrote:
>
> >
> > movntq instruction is supported by Geode CPU's, so use
> > fast_clear_page/fast_copy_page versions that have it.
>
> Is it actually faster for macro performance not just microbenchmarking ?

A COW intensive private mmap() benchmark shows the kernel spending
_more_ time inside mmx_copy_page() with movntq than with movq.

So its not clear whether the patch is actually a win, please drop it.

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