Which command demonstrates starting a process with the default niceness value?

• A. renice
• B. nice
• C. ps
• D. top

Answer: (B)

Niceness controls scheduling priority for processes. When a new process starts, it inherits or is given a niceness value, with the default being 0. The command designed to launch a program with a (potential) niceness adjustment is the one that handles this at start. Using the nice command starts a program with a modified niceness value; if you specify an adjustment of 0 (nice -n 0 command), you’re effectively starting with the default niceness. In practice, this demonstrates starting a process with the niceness concept in play. The other tools don’t start new processes with a niceness at launch: renice changes the niceness of existing processes, while ps and top are for viewing running processes, not launching them.