Thus a process, run with nice +15, will receive 25% of the CPU time allocated to a normal-priority process: (20 − 15)/(20 − 0) = 0.25. On the BSD 4.x scheduler, on the other hand, the ratio in the same example is about ten to one. Similar commands The related renice program can be used to change the priority of a process that is already running. Linux also has an ionice program, which affects scheduling of I/O rather than CPU time. See also kill ps top ionice from util-linux (see manual for disk storage I/O priorities) References External links Unix SUS2008 utilities Unix process- and task-management-related software