term% cat index.txt VMSTAT(8) System Manager's Manual VMSTAT(8)
NAME
vmstat - report virtual memory statistics
SYNOPSIS
vmstat [ -fs ] [ interval [ count ] ]
DESCRIPTION
Vmstat normally reports certain statistics kept about process, virtual
memory, disk, trap and cpu activity. Option -f reports on forks since
system startup and the number of pages of virtual memory involved. Op‐
tion -s reports on paging events since boot.
In the absence of other options, the optional interval argument 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 be‐
long to processes that have run in the last 20 seconds.
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)
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
VMSTAT(8)