$ curl cheat.sh/
# ionice
# Get or set program I/O scheduling class and priority.
# Scheduling classes: 1 (realtime), 2 (best-effort), 3 (idle).
# Priority levels: 0 (the highest) - 7 (the lowest).
# More information: <https://manned.org/ionice>.

# Set I/O scheduling class of a running process:
ionice -c scheduling_class -p pid

# Run a command with custom I/O scheduling class and priority:
ionice -c scheduling_class -n priority command

# Print the I/O scheduling class and priority of a running process:
ionice -p pid

$
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