https://bugs.freedesktop.org/show_bug.cgi?id=44523

Bug #: 44523 Summary: nexuiz perf regression since u_vbuf: implement another upload codepath which unrolls indices Classification: Unclassified Product: Mesa Version: git Platform: x86 (IA32) OS/Version: Linux (All) Status: NEW Severity: normal Priority: medium Component: Drivers/Gallium/r600 AssignedTo: dri-devel@lists.freedesktop.org ReportedBy: lists@andyfurniss.entadsl.com

d-r-t kernel, HD4890.

Since -

commit ce44bae366ade59fb2dbdfbfe5a1ab8d24518a57 Author: Marek Olšák maraeo@gmail.com Date: Tue Jan 3 22:01:03 2012 +0100

u_vbuf: implement another upload codepath which unrolls indices

Improves performance from cca 1 fps to 23 fps in Cogs. This new codepath is not always used, instead, there is a heuristic which determines whether to use it. Using translate for uploads is generally slower than what we have had already, it's a win only in a few cases.

I get quite a noticeable perf regression running demo1 in nexuiz.

Other games (openarena,ut2004 demo, etqw) seem unaffected

91.2740132 fps, one-second fps min/avg/max: 50 99 231 (90 seconds)

to

55.6802612 fps, one-second fps min/avg/max: 19 69 231 (90 seconds)

Sometimes I saw a couple of short (1/4 sec) stalls as well, which gave worse results, above was without stalls.