BFS is optimized for real use, not for throwing -j512 kernel builds at it. If you really intend to run such a massive workload (why?), you would run it SCHED_IDLEPRIO or nice 19 (or both). If you have written a new scheduler, posting information about how it handles -j128 "better" than the others says absolutely nothing about the merit of that scheduler. The only thing it says is that it handles something no one needs but doesn't say anything about how it handles stuff people actually *do* need.