VMSTAT(8) VMSTAT(8)
NAME
vmstat - report virtual memory statistics
SYNOPSIS
vmstat [ -fs ] [ interval [ count ] ]
DESCRIPTION
Vmstat normally reports certain statistics kept about pro-
cess, virtual memory, disk, trap and cpu activity. Option
-f reports on forks since system startup and the number of
pages of virtual memory involved. Option -s reports on pag-
ing events since boot.
In the absence of other options, the optional interval argu-
ment causes vmstat to report once each interval seconds,
repeated count times or forever.
The default format fields are:
Procs: information about numbers of processes in various
states.
R in run queue
B blocked for resources (i/o, paging, etc.)
W runnable or short sleeper (< 20 secs) but swapped
Memory: usage of virtual and real memory. `Active' virtual
pages belong oto processes that have run in the last 20 sec-
onds.
AVM active virtual pages
FRE size of the free list
Page: paging activity, averaged each five seconds, and given
in units per second.
RE page reclaims (simulating reference bits)
PI page-in events
PO page-out events
FR pages freed per second
DE anticipated short term memory shortfall
SR scan rate: pageout daemon rpm
Disk: operations per second. Typically paging is split
across several drives. The drive names are ephemeral: ask a
guru.
Faults: trap/interrupt rate averages per second over last 5
seconds.
IN (non clock) device interrupts per second
SY system calls per second
PD pseudo-dma interrupts on DZ
CS cpu context switch rate (switches/sec)
VMSTAT(8) VMSTAT(8)
Cpu: breakdown of percentage usage of CPU time
US user time for normal and low priority processes
SY system time
ID cpu idle
FILES
/dev/kmem, /unix