The Procps package contains the free, kill, oldps, ps, skill, snice, sysctl, tload, top, uptime, vmstat, w and watch programs.
free displays the total amount of free and used physical and swap memory in the system, as well as the shared memory and buffers used by the kernel.
kills sends signals to processes.
ps gives a snapshot of the current processes.
skill sends signals to process matching a criteria.
snice changes the scheduling priority for process matching a criteria.
sysctl modifies kernel parameters at runtime.
tload prints a graph of the current system load average to the specified tty (or the tty of the tload process if none is specified).
top provides an ongoing look at processor activity in real time.
uptime gives a one line display of the following information: the current time, how long the system has been running, how many users are currently logged on, and the system load averages for the past 1, 5, and 15 minutes.
vmstat reports information about processes, memory, paging, block IO, traps, and cpu activity.
w displays information about the users currently on the machine, and their processes.
watch runs command repeatedly, displaying its output (the first screen full).