FIrst, the specs. I am running a 12 core 2.93 GHz mac pro with 16GB ram, and the 5870 GPU, my project file is a 1 minute 15 second 237 MB ProRes 422 video at 720x480 and 29.97 fps stored on my media drive which is a RAID with 227.5 MB/s read and 210.3 MB/s write. I'm running AE CS 5.5 (10.5.0.253) on OS X 10.6.8.
Applying only the Add Grain effect with all default settings, when I play back I get around 5.5 fps (final output) or 17 fps (preview). If I watch activity monitor, I never max out the RAM I have assigned to AE, and while it utilizes more than one core, it never maxes any of them out. This seems low to me, is this all I should expect out of this machine? Is there anything I can do to make it faster?
when you say 'play back' are you hitting spacebar to do a preview or zero on the numbers pad to do a ram preview? with ae, you'll pretty much always want to do a ram preview (hit zero rather than spacebar).
ram previews will almost always playback in realtime after the preview is cached to ram. the amount/duration of preview is dependent on the amount of ram you have, the frame size and the frame rate of the comp, factored by the resolution down-sampling if not set to 'full'.... basically a 720x480 frame takes up 1mb of ram. at 29.97 fps, 1 second would take 30mb, etc, etc...
processing time/performance is another thing all together... if your multiprocessing settings are set fairly well you should normally get pretty high cpu levels. follow the links on this page to get a good idea of how to configure you preferences:
I was using space bar and not a RAM preview, that did make it better. My settings were close to what Adobe recommends, I've tweaked them a bit based on what you linked, thanks. I know I need more RAM, thats going to be in the offing on 2012s budget. I'm just learning AE, having been tasked with adding this skillset to what we already offer our corporate clients, so I don't really have any idea what normal performance looks like, so any tips/tweaks are appreciated.