I/O Priority Using "ionice"

• ionice allows us to give priority to I/O generated by certain processes.
• There are 3 level classes - real-time, best-effort and Idle.
  • Real-time - gets absolute priorities above others. there are 8 real-time levels. CAN CHOKE ALL OTHER I/O!
  • Best-effort - the default class. A longer time-slice is defined for each level. Default level is 4. Time-slice also affected by process "nice" level.
  • Idle - will be allowed I/O access only when the other classes do not have any pending I/O.
• Can change I/O priority of running processes, or start new processes with a given priority.

Originally written by guy keren