[unix-history] / usr / man / man1 / vmstat.1

.TH VMSTAT 1 11/13/79
.UC
.SH NAME
vmstat \- report virtual memory statistics
.SH SYNOPSIS
.B vmstat
[
.B \-fs
]
[ interval [ count ] ]
.SH DESCRIPTION
.I Vmstat
delves into the system and reports certain statistics kept about
process, virtual memory, disk and cpu activity.
If given a
.B \-f
argument, it reports on the number of
.I forks
and
.I vforks
since system startup and the number of pages of virtual memory involved in each
kind of fork.
If given a
.B \-s
argument, it prints the contents
of the
.I sum
structure, given the total number of several kinds of paging related
events which have occurred since boot.
.PP
If none of these options are given,
.I vmstat
will report in a (usually) iterative fashion on the virtual memory
activity in the system.
In this case, the optional
.I interval
argument causes
.I vmstat
to report once each
.I interval
seconds;
``vmstat 5'' will print what the system is doing every five seconds;
this is a good choice of printing interval since this is how often
the statistics are sampled in the system.
If a
.I count
is given, the statistics are repeated
.I count
times.
The fields are:
.PP
Procs: information about numbers of processes in various states.
.sp .1i
.ta +1i
.nf
RQ	in run queue
DW	sleeping on short event (disk wait)
PW	in page wait
SL	sleeping for short time, and in main memory
SW	runnable or sleeping for a short time, but swapped out
.fi
.sp .1i
Virtual: information about the state of virtual memory in the system.
.sp .1i
.ta +1i
.nf
AVM	active virtual pages
TX	percentage of active pages which were shared text pages
.fi
.sp .1i
Real: information about the state of real memory in the system.
.sp .1i
.ta +1i
.nf
USE	page frames in use for data+text+stack of active processes
TX	percentage of USE which is text (shared program) pages
FRE	size of the free list
.fi
.sp .1i
Fault: information about page faults and paging activity.
These are averaged each five seconds, and given in units per second.
.sp .1i
.ta +1i
.nf
RE	page reclaims (simulating reference bits)
PI	pages paged in
PO	dirty page write back rate (pages per second)
FR	rate at which free list is replenished (pages per second)
SR	scan rate: pageout daemon rpm (this is in revs/minute)
.fi
.sp .1i
Swp: information about the activity of the swap daemon (process 0).
.sp .1i
.ta +1i
.nf
I	process swap in rate (processes per 10 seconds)
O	process swap out rate (processes per 10 seconds)
.fi
.sp .1i
Disk: operations per second (this field is system dependent).
.sp .1i
.ta +1i
.nf
RP	/usr (user) file transactions and root file activity
RM	paging and /tmp (temporary) file activity
.fi
.sp .1i
Cpu: cpu context switch rate and breakdown of cpu 
usage by percentage in last few seconds.
.sp .1i
.ta +1i
.nf
CS	cpu context switch rate in switches per second
.sp .1i
US	user time
SY	system time
ID	cpu idle
.fi
.PP
Any time not accounted for by US+SY+ID is given to low priority jobs.
.SH FILES
/dev/kmem, /vmunix
.SH SEE ALSO
The section on configuration in
.I "Setting up the Virtual Memory Extensions to the UNIX System"
by O. Babaoglu and W. Joy
.SH AUTHORS
William Joy and Ozalp Babaoglu
.SH BUGS
So many numbers print out that its sometimes hard to figure out what to watch.
Commit	Line	Data
05459600 BJ	1	.TH VMSTAT 1 11/13/79
	2	.UC
	3	.SH NAME
	4	vmstat \- report virtual memory statistics
	5	.SH SYNOPSIS
	6	.B vmstat
	7	[
	8	.B \-fs
	9	]
	10	[ interval [ count ] ]
	11	.SH DESCRIPTION
	12	.I Vmstat
	13	delves into the system and reports certain statistics kept about
	14	process, virtual memory, disk and cpu activity.
	15	If given a
	16	.B \-f
	17	argument, it reports on the number of
	18	.I forks
	19	and
	20	.I vforks
	21	since system startup and the number of pages of virtual memory involved in each
	22	kind of fork.
	23	If given a
	24	.B \-s
	25	argument, it prints the contents
	26	of the
	27	.I sum
	28	structure, given the total number of several kinds of paging related
	29	events which have occurred since boot.
	30	.PP
	31	If none of these options are given,
	32	.I vmstat
	33	will report in a (usually) iterative fashion on the virtual memory
	34	activity in the system.
	35	In this case, the optional
	36	.I interval
	37	argument causes
	38	.I vmstat
	39	to report once each
	40	.I interval
	41	seconds;
	42	``vmstat 5'' will print what the system is doing every five seconds;
	43	this is a good choice of printing interval since this is how often
	44	the statistics are sampled in the system.
	45	If a
	46	.I count
	47	is given, the statistics are repeated
	48	.I count
	49	times.
	50	The fields are:
	51	.PP
	52	Procs: information about numbers of processes in various states.
	53	.sp .1i
	54	.ta +1i
	55	.nf
	56	RQ in run queue
	57	DW sleeping on short event (disk wait)
	58	PW in page wait
	59	SL sleeping for short time, and in main memory
	60	SW runnable or sleeping for a short time, but swapped out
	61	.fi
	62	.sp .1i
	63	Virtual: information about the state of virtual memory in the system.
	64	.sp .1i
65	.ta +1i
66	.nf
67	AVM active virtual pages
68	TX percentage of active pages which were shared text pages
69	.fi
70	.sp .1i
71	Real: information about the state of real memory in the system.
72	.sp .1i
73	.ta +1i
74	.nf
75	USE page frames in use for data+text+stack of active processes
76	TX percentage of USE which is text (shared program) pages
77	FRE size of the free list
78	.fi
79	.sp .1i
80	Fault: information about page faults and paging activity.
81	These are averaged each five seconds, and given in units per second.
82	.sp .1i
83	.ta +1i
84	.nf
85	RE page reclaims (simulating reference bits)
86	PI pages paged in
87	PO dirty page write back rate (pages per second)
88	FR rate at which free list is replenished (pages per second)
89	SR scan rate: pageout daemon rpm (this is in revs/minute)
90	.fi
91	.sp .1i
92	Swp: information about the activity of the swap daemon (process 0).
93	.sp .1i
94	.ta +1i
95	.nf
96	I process swap in rate (processes per 10 seconds)
97	O process swap out rate (processes per 10 seconds)
98	.fi
99	.sp .1i
100	Disk: operations per second (this field is system dependent).
101	.sp .1i
102	.ta +1i
103	.nf
104	RP /usr (user) file transactions and root file activity
105	RM paging and /tmp (temporary) file activity
106	.fi
107	.sp .1i
108	Cpu: cpu context switch rate and breakdown of cpu
109	usage by percentage in last few seconds.
110	.sp .1i
111	.ta +1i
112	.nf
113	CS cpu context switch rate in switches per second
114	.sp .1i
115	US user time
116	SY system time
117	ID cpu idle
118	.fi
119	.PP
120	Any time not accounted for by US+SY+ID is given to low priority jobs.
121	.SH FILES
122	/dev/kmem, /vmunix
123	.SH SEE ALSO
124	The section on configuration in
125	.I "Setting up the Virtual Memory Extensions to the UNIX System"
126	by O. Babaoglu and W. Joy
127	.SH AUTHORS
128	William Joy and Ozalp Babaoglu
129	.SH BUGS
130	So many numbers print out that its sometimes hard to figure out what to watch.