renice:tldr:f373a

The command "renice" is used to change the priority (niceness) of a running process on a Unix-like system. The command renice is short for "re-prioritize a process".

Here is an explanation of the individual components of the command:

• "renice": The command itself.
• "-n": A flag that specifies the new niceness value. The ${niceness_value} represents the niceness level that you want to set for the process. A lower niceness value indicates higher priority; values range from -20 (highest priority) to 19 (lowest priority).
• "${niceness_value}": This is the actual value you want to assign to the process's niceness level.
• "--pgrp": Another flag that indicates the process group. The ${process_group} represents the process group ID (PGID) of the group of processes you want to target for renice.
• "${process_group}": This is the actual process group ID you want to target for renice.

In summary, the renice command with the specified flags and parameters allows you to adjust the priority (niceness) of a specific process group to the desired niceness value.