Recently installed instance of SuiteCRM 8.1.2 is incredibly slow

Hey there,
so I reinstalled SuiteCRM on the server because of some issues that I could not fix. Now the software is incredible slow (30+s seconds of loading animation on page switch) but the CPU and RAM utilisation of the server sits at basically zero for the entire duration of the “loading” until a short spikes seconds before it finishes.

Any ideas what could cause this? Thanks!

You might need to tweak your host a little bit.

Starting with making sure everything is fully compatible:

Then the tweaks: