Preview extremely slow but normal when I unfocus After Effects (Need help)

[Jesse271856579bw3]

Im having this weird problem where my preview is really slow but when I open a different application on my PC it speeds back up and its normal until I pause/play again. In the video I was still using AE 22, after updating to the latest version the problem still exists, is this a bug or a problem with my settings?

So far I tried:

-Updating

-Clearing cache

-Precomposing

-Lowering preview resolution, acts the same way

-Disabling Multi-Frame Rendering

-Enabling reduce cash size

AE has 26gb ram available and I disabled hardware accelerated decoding because it was giving me lots of green frames

[Rick Gerard · Accepted solution]

You have a comp that is 5 minutes long and 60 fps. That's a very unusual comp length and an uncommon frame rate. The standard for streaming and social media is 24, 25, or 30. 

Are you trying to use AE as a video editing app? It is not one, never was, and probably never will be. It's designed to make shots that you can edit in a movie using an NLE like Premiere Pro. The average AE comp in a professional setting is only one shot. Occasionally, when you need to do a transition between shots that can't be done in an NLE, you have two. I've made lots of these transitions, but my comps are only as long as the transitions. Sometimes they are only 10 or 15 frames long. 

That said, you might be able to get better performance if you

• Preferences by pressing Alt/Option + Ctrl/Cmnd + ;
• Navigate to Memory and Performance
• Set allocation to other apps as an even multiple of 4 GB (4, 8, 12, for example)

Then try and run previews again. 

It would be highly unusual for anything but a very $$$$$ and powerful machine to be able to consistently playback a five-minute video. When you bring another app to the front, AE possibly stops looking for things to render. When AE is in the foreground, AE looks at every pixel on every layer for every frame. 

[Jesse271856579bw3]

Aha, I changed the length of the comp to 5:30min because I was searching for a piece in a 5 minute clip and never thought a thing about it, now that I've changed it back to 1 minute and it resolved the issue completely, never knew that 4 minutes of nothing in a comp could decrease performance. Thankyou