ionice

Set I/O scheduling class

low risk

interactive breakdown — edit the command and press Explain
$ 
⚠ Risks & cautions
What it does

Control disk I/O priority of a process. See the flags and examples below, and run `man ionice` for the full reference.

Common flags
FlagMeaning
-cClass (1 realtime, 2 best-effort, 3 idle)
-nPriority within class
Examples
ionice -c3 rsync -a /src /dstRun copy at idle I/O priority · explain & risk-check →
Related
nice iotop
Open the full explainer →More in System & Processes

Reference text is hand-written and may be incomplete — check man ionice for your version. Test destructive commands on a non-production system first.