AE CS4 issue on Mac Pro Nehalem 2.26 with 12 Gigs RAM

[Kevin Camp]

which property are you looking at when it says 1.79gb… is it the ‘foreground memory usage’? and are you saying that you can’t get it to go higher than 1.79gb when you drag the slider from faster rendering to longer previews…?

if so, that isn’t a problem and that is not the total ram that ae is using, it is just the amount that it is using for the rm cache… to compare it with cs3, you are adjusting the max ram cache value. so, in cs3 when you have a max ram usage for 3gb and a max ram cache of 60%, your ram cache is 1.8gb… that is the same as the foreground memory usage in cs4…

[hemant kapoor] “total RAM used always shows no more than 5 Gigs in activity monitor”

i believe in this case, the 5gb of ram, doesn’t mean that ae was limited to only 5gb, it means that ae only needed to used 5gb for that render. try setting the same comp to 32bpc color or enlarging the frame size and see if the ram usage goes up in the activity monitor.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Hemant Kapoor]

Kevin,

You are bang on. I checked in CS3 version. The RAM Cahce size in indeed 1.8 GB. Allow me to explain the issue I am facing which got me investigating all this. I had MAc Pro 2.8 Ghz 2008 model with 16 GB of RAM. I could easily do long enough RAM previews. Recently I upgrade my machine to 2009 2.26 nehalem model. Now Ram previews cannot go above 2-3 seconds on a average. When I enable multiprocessing, the background RAM and total RAM usage in CS4 does increase. But neither does the foreground RAM increase ( which I believe is responsible for longer RAM previews, correct me if I’m wrong) nor does the total RAM usage for AE goes above 5 GB at the most. This is why I was trying to look for an option to increase foreground RAM size.

Now from what I understand more the amount of RAM I have longer RAM previews I can get. But I can clearly see that is not the case here. I still have 7 GB of RAM idling when RAM preview starts trailing.

[Kevin Camp]

no matter how much ram you have, ae (the foreground process) will only use 3gb of ram (on a mac… you can get bit more on a pc). this 3gb is divided, with part of it going to the ram cache and part of it going to buffering for rendering and such… so your ram previews are limited to the 1.8gb of ram to store the preview no matter how much extra ram is available (in cs3 and earlier, you could increase that, but it was not recommended to go beyond the default 60%, lower was ok).

however, i would think that you should be able to render more that 2-3 seconds to available ram…

i’m curious… on your new mac, in the multiprocessing settings, how many cores does it say are installed? i’ve heard that with the new hyper-threaded cpus you’ll see 16 cores on an 8-core machine. even if the preference doesn’t say 16, do you see 16 aeselflink processes start up during a render? if you do, you may be limiting the amount of ram to the foreground process if all 16 cores are available for multiprocessing (now you have 16 cores splitting up your 12gb of ram). you may want to try reducing the number of cores…. although i don’t believe that was the way cs3 worked.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Hemant Kapoor]

Thanks for the response Kevin. Yes, In CS4 it does say 16 cpus available. I have try reducing the number of cpus and that doesnt seem to help. I did notice that this problem existed with a new project I recently started working on. This project has only one layer (footage) with keylight and some contrast/color correction applied. Funny part is that CS4 doesnt even disk cache for this particular project. I tried my older projects which had multiple layers and they seem to work fine with help from disk cache. I tried various combinations of cpu numbers and it all gives same 2-3 sec of ram preview. I’m seriously considering going back to my previous mac pro model.

[Kevin Camp]

[hemant kapoor] “I’m seriously considering going back to my previous mac pro model.”

have you tried cs3 on the new mac? since the whole multiprocessing and memory preferences changed in cs4, i’m curious if cs3 with your the settings from your previous mac may work better.

[hemant kapoor] “CS4 doesnt even disk cache for this particular project.”

sorry, but i have to ask… you do have disk caching enabled for cs4? it’s in a separate cache preference now, so i just wanted to be sure…

you might also want to try posting on adobe’s ae forum to see what they may have to say…

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Hemant Kapoor]

Hey Kevin,

Sorry for taking off there. I was away for some time. To answer your question, yes, CS3 also displays same behavior. I just cant seem to get more than 3-4 secs of ram preview no matter what combination of multi cpu / ram configuration I use.

[Mike Throck]

I had this problem too with the exact same problem. For me the problem was I had the slider cranked to “Faster RAM preview”, when I put it back near the middle I was able to RAM preview much more of the composition.

[Ted Maynard]

On the Preview palette, set the resolution to Half. That should quadruple your previews. Also, according to Adobe, you may have to increase the Maximum allocation per CPU to at least 1GB if working in HD or with large pixel sizes.

“Minimum Allocation Per CPU
Specifies the minimum amount of RAM that will be allocated to each background process, each of which runs on its own CPU (processor core). Setting this value lower can allow more CPUs to be used simultaneously with a limited amount of RAM. However, if you set this value too low for the kinds of frames that you are rendering, then the background processes will fail to render frames at all, and only the foreground process will be used to render frames. For example, you should not set this value to 0.5 GB if you are rendering frames with the pixel dimensions of high-definition television or digital cinema.”