Vmstat
External
Internal
Overview
Reports virtual memory and other system statistics.
Output
procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu----- r b swpd free buff cache si so bi bo in cs us sy id wa st 2 0 0 778480 700 156424 0 0 122 4 29 64 0 0 98 0 1
procs
r
The number of runnable processes (running or waiting for run time).
b
The number of processes in uninterruptible sleep. This is the size of the "wait queue" - processes that are waiting for I/O (disk, network, user input, etc.)
memory
swpd
The amount of virtual memory used. Represents how many blocks are swapped out to disk (paged). The same information can be obtained from /proc/swaps. To get the amount of swapped memory, in bytes, multiply the swpd value with the size of the block. This is how you can get the size of the page, in bytes.
free
The amount of free memory.
buff
The amount of memory used as buffers.
cache
The amount of memory used as cache.
swap
si
Amount of memory swapped in from disk.
so
Amount of memory swapped to disk.
IO
b
Blocks received from a block device (blocks/s).
bo
Blocks sent to a block device (blocks/s).
system
in
The number of interrupts per second, including the clock.
cs
The number of context switches per second.
CPU
us
Percentages of total CPU time spent running non-kernel code (user time, including nice time).
sy
Percentages of total CPU time spent running kernel code (system time).
id
Percentages of total CPU time spent idle.
wa
Percentages of total CPU time spent waiting for IO.
st
Time stolen from a virtual machine.
Continuous Readings
vmstat 1