[Qt-creator] Sensible make -j X?

[Jason H]

In this world, where both phones and computers are averaging 4 cores (or more) does it make sense to ever not default make to 1 thread? I can understand that some situations can't have multi-threaded builds, but I believe they are in the minority now. I find that a good value for -j is N*2 where N is the number of cores (since there is a lot of i/o delay from loading all the headers)

It would be nice if this was populated from the get-go. I believe it's stored in the .user file? Is there a way to set it in the .pro file? I work in iOS/Android/Desktop, so it's kinda silly to have to set this 6 times (debug/release) in the same project!