When I add multiple CH dynamic links to an AE project file, my RAM increases significantly even for those CH links not being used in the specific timeline. I try to reduce RAM usage by putting AE playback on 1/3, close CH when AE is being used and AE cache is on an Samsung T5 portable SSD. I would like to keep my project in one AE file but maybe there is a recommended limit on the number of CH dynamic links per AE file? Thanks
Here is my hardware information:
CPU: i7 7700HQ 2.8Ghz 4 core
GPU: Nvidia Geforce GTX 1050
OS: Windows 10
There's no recommended limit, but if your project is using too many resources then you'll have to back off or do things to compensate. Even if your Ch projects aren't in a comp they're still being loaded and project launch so they can quickly be accessed. You could always turn them into proxies to temporarily replace them with a video (which will also result in better performance) or render out a video or image sequence directly from Character Animator. Having that live link between a comp is desireable, but it's also slow, so if you're finished working on one comp then I'd recommend replacing it with a video.
A proxy file is something that you're temporarily replacing your original or full resolution file with so you can work faster. Traditionally, this workflow is used for editing something like 4K or raw footage on a machine that can't handle the original files so you create lower res files to edit with and then replace those proxies with the originals during export. This is also used in After Effects in a number of ways, but in your case it would simply mean turning your Character Animator comp into a flattened video (using a format like ProRes, Cineform, or DNxHR) that will play back smoother. A checkbox will appear next to the item in the Project panel and when it's checked all instances of that comp will be referencing the proxy file, and when it's unchecked all instances will reference the original, Dynamically Linked comp. Here's some more info on that workflow: https://helpx.adobe.com/after-effects/using/footage-items.html#placeholders_and_proxies
Edit: That being said, what is the reason you're using Dynamic Link. Are you still updating these comps in Character Animator while you're compositng them in After Effects or are you finished animating them? If you're done making edits, or you're not actively updating them where you need to see a real-time change when flipping back and forth from CH to AE, you should definitely be rendering out your comps as videos via one of the many methods available to you—directly from Character Animator, by queueing to Media Encoder, or by using proxies as a means of rendering a full res file, rather than the traditional lower quality one.