Please file a detailed bug report.
Also, if you want us to help on this forum, we'll need more details. To begin with, what are your exact Memory & Multiprocessing preferences settings? Does changing any of these settings cause or prevent the behavior that you mention?
How much RAM do you have? What version of Mac OS X (e.g., 10.5.8, 10.6.3)? What kind of footage?
Thanks for the reply. I've been getting fewer problems by simply pacing myself before I RAM preview, but they have not entirely gone away. Here are my settings as of now.
Footage layers are hand drawn scans animated in 3-D space, but all on the same z plane (virtual animation stand - Reference Still Below). Very few effects. A lot of blending modes.
2 x 3.2 GHz Quad-Core Intel Xeon
12 GB RAM
OS X V 10.6.3
AE Memory Settings:
Installed RAM: 12 GB
RAM for other Apps: 3 GB
Render Multiple Frames Simult: ON
Installed CPUs: 8
CPUs reserved for other Apps: 0
RAM per Background CPU 2 GB
Actual CPUs used: 3
Media & Disk Cache Settings:
Enable Disk Cache ON
Max Disk Cache Size: 2000 MB
Write XMP IDs ON
Create Layer Markers ON
I have the same problem!?!?
I've been able to avoid these crashes by turning 'Render Multiple Frames Simultaneously' OFF. Which is a very annoying fix. I've got to hope that there is another answer out there in balancing RAM and processors and AE being able to identify what is safe to take or not.
Until then the mystery continues.
Any update on this? I'm having the exact same issue on 2010 MacPro tower (12 cores, 24GB of RAM). If I try to RAM preview with multiprocessing on, it crashes about 50% of the time (beach ball of death. Then, when I try to forcequit, the whole computer freezes)
We need a lot more information if we're going to help you. What exact version of After Effects are you using? What are your memory and multiprocessing settings? What OS? Tell us about your composition and source footage.
Okay...here we go...
After Effects Info:
Memory and Multiprocessing settings:
Installed RAM: 24 GB
RAM reserved for other applications: 3GB
RAM available for AE, PR, EN, Media Encoder: 21 GB
Render Multiple Frames Simultaneously is checked on:
CPS reserved for other applications: 6
RAM allocation per background CPU: 1GB
Actual CPUs that will be used: 18
Mac OS 10.6.7
2x2.93 GHX 6-Core Intel Xeon
24 GB 1333 MHZ DDR3
In terms of footage, this happens across all composition types and video footage types (ProRes, photo jpg, Sony XD-CAM EX, HD, SD) You name, it after effects will crash it! Again, this only happens if multiprocessing is turned on during RAM previews.
It's almost like AE is attempting to power up all the machine's processors, but just never quite gets there.