RAM preview issues

[Mortisfilm]

Hi all,

Recently set up a new Mac Pro 7,1 to replace my 2010 Mac Pro 5,1, and I'm in the process of upgrading my in-progress AfterEffects projects, which were built in AE 2017. These are complex projects with lots of stock footage and Photoshop layered elements, but they all run fine in my 2010 machine.

My new Mac has a 3.2 GHz 16-Core Intel Xeon W, 384 GB of RAM, an AMD Radeon Pro Vega II 32 GB GPU, which is running two LG UltraFine 5K displays at 60GHz. All of my projects, stock footage elements, Photoshop layered elements, and scratch disk are on M.2 SSD drives.

I initially installed AE 2020, but was having a persistant RAM preview issue where I couldn't preview more than 3 seconds of a full resolution 1920x1080 composition without the program freezing and giving me the dreaded color wheel -- I would have to force quit the software every time. 

I posted about this strange freezing issue on the forum a few days ago, along with a crash log, but didn't get any replies, so I decided to install AE 2019 to see if I could get a better result.

In AE2019, I'm able to get my RAM preview to load more than 3 seconds of footage, but the playback is not in real time. It plays super stuttery -- the comps were set up in 24 FPS, but they playback around 6-8 FPS. They're very complex, but I get this slow stuttery playback even when I have just a simple black solid isolated.

Super frustrating, but I know there must be some troubleshooting I can do to help solve the issue. Here are some things I've already done:

I have my "preview" menu set with "cache before playback" checked on. Both of my monitors are running at 60GHz, and my GPU supports running both monitors.

In the AE preferences, I've tried changing from "Mercury GPU Acceleration (Metal)" to "OpenGL" to "Software Only" -- no difference. 

I've also disabled all my 3rd party plug ins to see if that makes a difference and trashed my preferences, but the playback is still not close to realtime.

[Jose Panadero]

Check if you are using a lot of RAM in AE. If so, try to assign more RAM for other applications under After Effects > Preferences > Memory

[Mortisfilm]

Thank you for the suggestion.

I have 384 GB of installed RAM on my machine -- I had 12 GB reserved for other applications. After doubling it it 24 GB RAM reserved for other applicaitons, the RAM preview still stutters in AE2019. 

Oddly enough, the same project does *not* stutter in AE2020 (with either 12 or 24 GB of RAM reserved for other applications), but the project freezes when I try to preview more than 3 seconds of footage, and then I have to force-restart.

[Jose Panadero]

For the RAM, try to assign 100GB for other apps.

Any third party plugin installed? Have you tried to change the cache directory?

[Mortisfilm]

Plenty of 3rd party plug-ins, but I'm trying hard to get this resoloved, so I've removed all 3rd party plug-ins.

I have two large M.2 SSD drives (each one is setup as an 8TB RAID 0 drive), with about 4-5 TB of RAM available in each RAID 0 setup. I set the cache at 1000GB and I've tried it out on both RAID 0 arrays. 

I also increased the RAM assigned to other apps to 100GBs.

Unfortunately even with these changes, the RAM preview for AE2019 is still super stuttery -- 8 FPS/24, even with just a single solid solo-ed.

I can't figure it out. Should I not have set up my cache on an array of SSDs that are setup in RAID 0? Is that slowing down my performance somehow...?

[MehMeh123]

The slot to allocate more ram to Ae is greyed out on mine is it because i have a bad gpu?