Re: [patch 2/2] reduce tlb/cache flush times of agpgart memory allocation

[Arjan van de Ven <arjan@infradead.org>]

On Mon, 18 Aug 2008 09:21:12 +0800
"Li, Shaohua" <shaohua.li@intel.com> wrote:

> 
> >
> >it really needs something else instead; it needs airlied's array
> >allocator
> >otherwise you hit the second wall as well (the pat checks per page)
> Somebody should have a measurement. In my test, the real bottleneck
> is the cache flush. It appears flush cache page is slow if there are
> a lot of pages, In my patch, I use a wbinvd. This can be optimized to
> do wbinvd with a threshold. Maybe airlied can change his patch with
> this way.


it would be great if you had time to update his patch and this to
it...

and the logic probably should be "if there's more than X pags in the
the array, just use wbinvd".
Although wbinvd is very painful if you have 12Mb of cache and you wipe
it for all cores in the system ;-(



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