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Hands-on Lab·Red Hat Certified System Administrator

Process Priority with nice and renice

A one-line objective with one genuinely non-obvious rule: a normal user can make their own process nicer but cannot make it greedier again, not even back to where it started. Both directions are attempted here and the permission error is real.

Operating Running Systems Guide 26 of 67 Intermediate

Written against the versions above. Nice values run from **-20** (most favourable) to **19** (least). The `PRI` column that `ps` shows is derived from it and moves the opposite way, which is why raising `NI` lowers `PRI`. Only `NI` is settable.

Every command on this page runs on RHCSA-A01.
Server NameIP AddressOSRolesCPURAMHDD
RHCSA-A01192.168.0.31RHEL 10.0 (Coughlan)Practice node (graded) - spare /dev/sda2 Core4 GB50 GB + 15 GB

Before you start

  1. Where a process starts

  2. Which way an unprivileged user may move it

  3. Setting it at launch

Official sources