Which command allows you to change the priority of a running process?

The command that allows you to change the priority of a running process is "renice." This command is specifically designed to adjust the niceness value of an already running process, which in turn changes its scheduling priority. Lower niceness values correspond to higher priority, meaning the process will receive more CPU time compared to others with a higher niceness value.

Using "renice," you can specify the new niceness level along with the process ID (PID) of the process whose priority you want to change. This is particularly useful for system administrators and users looking to optimize performance or manage resource allocation on a multi-user system.

In contrast, "nice" is used to start a new process with a specified niceness value, "kill" is for terminating processes, and "top" is a utility for monitoring running processes and their resource usage but does not provide a direct way to change process priority without specific commands.