sar
sar is a Linux command in the Process Management category, rated intermediate difficulty. Collects and reports system activity (CPU, memory, network, disk). The syntax is sar [options] [interval] [count]. It returns system activity report. A practical example: sar -u 2 5 # CPU usage sar -r # Memory utilization sar -n DEV 2 # Network interfaces A close relative is ps, which reports a snapshot of current processes. A close relative is top, which real-time interactive process viewer. Updates every few seconds. A close relative is kill, which sends a signal to a process. Default signal is SIGTERM (terminate). More about this category: Linux process management commands — ps, top, kill, killall, pgrep, and more. Manage running processes and system resources. Related Process Management commands: ps, top, kill, killall, pgrep, pkill, nice, renice. This page is part of the free Linux Reference documentation covering 304+ commands, each with syntax, options, practical examples, and a difficulty rating.