Xcode12 real machine/simulator running project is very slow to solve

I just updated Xcode12, and found that the newly written project, the simulator and the real machine running project are stuck on the startup, which is very slow. It takes about a minute, which greatly affects work efficiency.

The solution is as follows:

1. Delete ~/Library/Developer/Xcode/iOS DeviceSupport/all folders in this directory

2. Select Xcode -->  Window--> Devices and Simulators, find the real device, right click to selectunpair the device

Restart Xcode, reconnect the device, rerun the application

Reprinted from: https://www.jianshu.com/p/0cce3ae0c2ec