Am Donnerstag, 9. Januar 2003 14:05 schrieb Petr Sebor: > Hello, > > somehow something got ommited, probably on my side. > [as I can tell from the end of the patch, since there are references > to removed code...] > > I'd like to send more cleanups if you are interested ;-)
Come along with it. > Btw: Unfortunatelly, I have noticed that the current SSE code tends to > be a little slower than the x86 path, at least on my XP2000+... not very > much, but still. I second that. > Maybe this is given by the AMD SSE implementation Could be. As I understand the AMD SSE implementation right, it isn't an extra CPU core but it use the 3DNow! infrastructure. > or more likely, because we don't smartly precache data while we can. Precaching is NOT by all means the fastest patch. See AMD's developer notes/optimization guides. There was discussion on LKM about a new memcopy routine. http://marc.theaimsgroup.com/?l=linux-kernel&m=103548024914815&w=2 [-] AMD recommends to perform memory copies with backward read operations instead of prefetch. http://208.15.46.63/events/gdc2002.htm [-] Some numbers: nuetzel/Entwicklung> ./athlon-DN 1600.156 MHz clear_page by 'normal_clear_page' took 12400 cycles (504.1 MB/s) clear_page by 'slow_zero_page' took 12412 cycles (503.6 MB/s) clear_page by 'fast_clear_page' took 9811 cycles (637.1 MB/s) clear_page by 'faster_clear_page' took 4239 cycles (1474.3 MB/s) copy_page by 'normal_copy_page' took 9231 cycles (677.1 MB/s) copy_page by 'slow_copy_page' took 9243 cycles (676.3 MB/s) copy_page by 'fast_copy_page' took 8318 cycles (751.4 MB/s) copy_page by 'faster_copy' took 5481 cycles (1140.3 MB/s) copy_page by 'even_faster' took 5545 cycles (1127.2 MB/s) copy_page by 'no_prefetch' took 4388 cycles (1424.3 MB/s) But maybe you should stop the CPU scanning on AMD after 3DNow! (normal/ext/prof) detection, so that AMD's run 3DNow! and not SSE. -Dieter ------------------------------------------------------- This SF.NET email is sponsored by: SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2 See! http://www.vasoftware.com _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
