Messages in this thread |  | | | Date | Tue, 17 Aug 2004 12:10:09 +0400 | | From | Andrey Panin <> | | Subject | Re: [PATCH] Use x86 SSE instructions for clear_page, copy_page |
| |
On 230, 08 17, 2004 at 09:27:51AM +0200, Arjan van de Ven wrote: > On Tue, 2004-08-17 at 08:13, Jens Maurer wrote: > > The attached patch (against kernel 2.6.8.1) enables using SSE > > instructions for copy_page and clear_page. > > > > A user-space test on my Pentium III 850 MHz shows a 3x speedup for > > clear_page (compared to the default "rep stosl"), and a 50% speedup > > for copy_page (compared to the default "rep movsl"). For a Pentium-4, > > the speedup is about 50% in both the clear_page and copy_page cases. > > > we used to have code like this in 2.4 but it got removed: the non > temperal store code is faster in a microbenchmark but has the > fundamental problem that it evics the data from the cpu cache; the > actual USE of the data thus is a LOT more expensive, result is that the > overall system performance goes down ;(
Did SSE clear_page() suffered from this issue too ?
-- Andrey Panin | Linux and UNIX system administrator pazke@donpac.ru | PGP key: wwwkeys.pgp.net[unhandled content-type:application/pgp-signature] |  |