vmstat

Print virtual memory statistics, repeating each DELAY seconds, COUNT times. (With no DELAY, prints one line. With no COUNT, repeats until killed.) Show processes running and blocked, kilobytes swapped, free, buffered, and cached, kilobytes swapped in and out per second, file disk blocks input and output per second, interrupts and context switches per second, percent of CPU time spent running user code, system code, idle, and awaiting I/O. First line is since system started, later lines are since last line.

vmstat [-n] [DELAY [COUNT]]

Report information about processes, memory, paging, block IO, traps, disks, and CPU activity.