Here’s two quick settings you can change on Xcode, one’s pretty minor, but the second one could be a big time saver. This first one will show you the build time on the activity bar, to enable it just enter this into the Terminal.
defaults write com.apple.dt.Xcode ShowBuildOperationDuration -bool true
To disable it, just change
The second one is to enable Xcode to use all cores available to your machine.
defaults write com.apple.dt.Xcode IDEBuildOperationMaxNumberOfConcurrentCompileTasks `sysctl -n hw.ncpu`
That last part specifies how many cores your machine has, for example, in my 15” Retina MacBook Pro [quad core i7], since it has hyperthreading it, it returns 8.