For normal processes, the kernel priority is simply +20 from the nice value. Thus a process with the neutral nice value of zero has a kernel priority of 20. This offset-by-20 is done so that a process with a nice value of -20, the highest priority nice value, receives a kernel priority of zero. Lower numeric values equal higher scheduling priority.

For realtime processes, the kernel priority is the process's real-time priority, but thePR column will simply print RT.

In some versions of the Linux kernel, the kernel priority could differ from the nice value, as the process scheduler applied a small bonus or punishment to interactive or processor-hogging tasks, respectively. In these older kernels, the value given by the PR column could differ from the nice value. This isn't true with the kernel's current scheduler, the Completely Fair Scheduler (CFS).