Host : iMac Pro 2017 3.2Ghz 8 Core Xeon / 32 Gb of RAM running last OS (no matter when you read it will be the last OS)

Guest: macOS last OS (no matter when you read it will be the last OS)

I need a Guest who is really have good performance, I played with the number of CPU ( from 2 to and the memory ( from 2 to but no matter what I do, simple operation like opening the launcher are slow.

Any idea. / suggestion how to optimized?