Slow performance after migration

I recently migrated from my Raspberry Pi 2 to a Raspberry Pi 4.

I did a full backup and restored everything on the new Pi and everything seems to work fine for now. But performance is real slow. Much slower than on my old Pi, which is weird.

The biggest problem seems to be the Node Red addon. Most of the times I try to start the UI the whole home assistant instance becomes unresponsive or even restarts.

I tried looking at the Logs but couldn’t find anything helpful.
I already tried uninstalling the Node-Red addon, but that didn’t help.

What is the best way to debug this?