Name

vmstat

Synopsis

                  vmstat [options] [interval [count]]

Print report on virtual memory statistics, including information on processes, memory, swap space, I/O, system and CPU usage. vmstat will first report average values since the last system reboot. If given a sampling period interval in seconds, it will print additional statistics for each interval. If specified, vmstat will exit when it has completed count reports. Otherwise, it will continue until it receives a Ctrl-C, printing a new header line each time it fills the screen.

Options

-n

Don’t print new header lines when the screen is full.

-V

Print version number, then exit.

Fields

procs
r

Processes waiting for run time.

b

Uninterruptable sleeping processes.

w

Swapped but runnable processes.

memory
swpd

Virtual memory used, in kilobytes.

free

Idle memory, in kilobytes.

buff

Memory used as buffers, in kilobytes.

swap
si

Memory swapped in from disk each second, in kilobytes.

so

Memory swapped out to disk each second, in kilobytes.

io
bi

Blocks sent to block devices each second.

bo

Blocks received from block devices each second.

system
in

Interrupts per second, including clock interrupts.

cs

Context switches per second.

cpu
us

Percentage of CPU time consumed by user processes.

sy

Percentage of CPU time consumed by system processes.

id

Percentage of CPU time spent idle.

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