I added parallel tests to our app last year. My 4 core/8 thread system runs the tests pretty well with a process count of 6. The suite runs about 4 times fast

I added parallel tests to our app last year. My 4 core/8 thread system runs the tests pretty well with a process count of 6. The suite runs about 4 times faster, which makes a real difference No need to wait for Rails 6 to get this boost