I updated to Xcode 10 about 1 year ago. When I run the project, Xcode is not smooth. I found that my Xcode cpu occupies 100%, and it will not be smooth for about 1 minute. I have to kill Xcode to ensure that my app can run. If I do this, I can't debug the app. After many attempts, I found that I was using the New build system, and when I switched to the Legacy build system, it went smoothly. Until recently when I upgraded to Xcode 12, I found that the Legacy build system was marked as deprecated. I don't know how I can improve my project in the future. If you use the New build system to debug the project, it is almost impossible for developers to use.
