OS X 10.6.3 Performance

OS X 10.6.3 is out. Besides adding a bunch of OpenGL extensions*, it looks like vertex performance is improved on nVidia hardware. My quick tests compare 10.5.8 to 10.6.3 (since I no longer have a 10.6.2 partition) and show a 15-30% improvement. If you have 10.5 and an 8800 you may want to consider updating your OS.

I also discovered that --fps_test=3 produces unreliable results because...wait for it...the deer and birds are randomized. If they show up during the fps test, you get hit with a performance penalty. I am working to correct this and may have to recut the time demo to work around this behavior.

If you are trying to time the sim via --fps_test=3, I suggest running the test multiple times - you should see "fast" runs and "slow" runs depending on our feathered and four-legged friends.

Phoronix reported a performance penalty with the new update; I do not know the cause of this or whether the fps_test=3 bug could be causing it. But their test setup is very different than mine - a GeForce 9400 on a big screen, which really tests shading power. My setup (an 8800 on a small screen) tests vertex throughput, since that has been my main concern with NV drivers.

My suggestion is to use --fps_test=2 if you want to differential 10.6.2 vs. 10.6.3. I'll try to run some additional bench-marks soon!

EDIT: Follow-up. I set the X-Plane 945 time demo to 2560 x 1024, 16x FSAA, and all shaders on (e.g. let's use some fill rate). I put the Cirrus jet on runway 8 at LOWI, then set paused forward full screen no HUD. In this configuration, I see these results:

Objects  10.5.8   10.6.3
none     85 fps   100 fps
a lot    46 fps   61 fps
tons     37 fps   42 fps

Note that in the "no objects" case the sim is fill-rate bound - in the other two it is vertex bound. So it looks to me like 10.6.3 is faster than 10.5.8 for both CPU use/object throughput and perhaps fill rate (or at least, fill-rate heavy cases don't appear to be worse).

* These extensions represent Apple and the graphics card company creating software interface to fully unlock the graphics card's abilities.