[Qt-creator] "-j" options to make. Where do they come from? Can I change the value?

[Toralf Lund]

I'm using Qt Creator on a system that has 4 CPU cores. It seams like 
that means "make" will always be run with argument "-j4". Is there a way 
I can change the number 4 to something smaller? Where does the option 
come from anyway?

A problem I have is that certain compile or link steps will use all the 
capacity of one core, and parallel jobs typically start on separate 
cores. If I have 4 jobs with 4 cores, that can mean all of them are 
saturated, and the system becomes completely unresponsive. Meaning I 
have to just sit and wait for the build to finish, while I prefer to run 
it "in the background" (even if it it takes longer that way) and 
continue to work on something else.

OS is CentOS Stream 8.

- Toralf