Hello,
I am currently running on 2018.3, and have not had any issues with this over 2 years. Randomly my Alteryx started not responding, so I closed the program and reset my computer. Now every time I make one action within a workflow it is freezing and going to the "not responding" phase for about 3-5 minutes per action. I am dealing with large datasets so I assumed it was just that workflow. I tried to test this with just a blank canvas and a small data sample, where even just joining this data to a union tool took over 5 minutes.
Not sure what the course of action here should be or if it would be beneficial to just uninstall and reinstall.