Hi!
When I run Spine 3.8 (current version) - my Mac OSX system becomes slow and unresponsive.

It seems to hog an important resource, because tabs in chrome start not loading 'n stuff. What's weird is that other apps consume similar amounts of RAM and CPU but do not bring my system to it's knees like this, and this was not the case pre 3.8.

<Edit:> It could be a GPU thing, as I think it behaves extra bad when is Illustrator also running.

This is on a 2015 i7 4GHz retina iMac, 32GB ram, 2GB RadeonR9 M290X GPU.

How can I help investigate this?

Sorry for the troubles and the late reply! What macOS version are you using? I run both Mojave and Catalina on MBPs which are a bit less beefy than your iMac. As with all such issues I'm of course not able to reproduce the slow down :/

Do you have any background apps on (assistive things, screen grabbers, window tiling, etc.) that could interfere with Spine? Pens/tables maybe? If so, try closing/disconnecting them one at a time and see if it changes the performance issue.

Thanks for having a look!
I'm still on Mojave, by the way.

Disabling the Anti Aliasing in the graphics settings made a big difference, as did, possibly, disabling "bettertouch tool" - but I'm enjoying my responsive system with running spine too much to do a deep dive right now

Thanks again!

Thanks for identifying the potentially interfering system parts. I'll see if I can figure out what they do that makes Spine eat your Mac. Glad we have a workaround for now though.