NAME
systat - display system statistics on a crt

SYNOPSIS
systat [ -display ] [ refresh-interval ]

DESCRIPTION
Systat displays various system statistics in a screen oriented
fashion using the curses screen display library, curses(3).

While systat is running the screen is usually divided into two
windows (an exception is the vmstat(1) display which uses the
entire screen). The upper window depicts the current system load
average. The information displayed in the lower window may vary,
depending on user commands. The last line on the screen is
reserved for user input and error messages.

By default systat displays the processes getting the largest
percentage of the processor in the lower window. Other displays
show swap space usage, disk i/o statistics (a la iostat(1)),
virtual memory statistics (a la vmstat(1)), network "mbuf"
utilization, and network connections (a la netstat(1)).

Input is interpreted at two different levels. A "global" command
interpreter processes all keyboard input. If this command
interpreter fails to recognize a command, the input line is passed
to a per-display command interpreter. This allows each display to
have certain display-specific commands.

Command line options:

refresh_interval
-display

The - flag expects display to be one of: pigs, iostat, swap, mbufs,
vmstat or netstat. These displays can also be requested
interactively (without the - ) and are described in full detail
below.

refresh-interval
The refresh-value specifies the screen refresh time interval
in seconds.

Certain characters cause immediate action by systat. These are:

^L Refresh the screen.

^G Print the name of the current "display" being shown in the
lower window and the refresh interval.

: Move the cursor to the command line and interpret the input
line typed as a command. While entering a command the
current character erase, word erase, and line kill
characters may be used.

The following commands are interpreted by the "global" command
interpreter.

help Print the names of the available displays on the command
line.

load Print the load average over the past 1, 5, and 15 minutes on
the command line.

stop Stop refreshing the screen.

[ start ] [number ]
Start (continue) refreshing the screen. If a second,
numeric, argument is provided it is interpreted as a refresh
interval (in seconds). Supplying only a number will set the
refresh interval to this value.

quit Exit systat. (This may be abbreviated to q.)

The available displays are:

pigs Display, in the lower window, those processes resident in
main memory and getting the largest portion of the processor
(the default display). When less than 100% of the processor
is scheduled to user processes, the remaining time is
accounted to the "idle" process.

iostat Display, in the lower window, statistics about processor use
and disk throughput. Statistics on processor use appear as
bar graphs of the amount of time executing in user mode
("user"), in user mode running low priority processes
("nice"), in system mode ("system"), and idle
("idle"). Statistics on disk throughput show, for each
drive, kilobytes of data transferred, number of disk
transactions performed, and average seek time (in
milliseconds). This information may be displayed as bar
graphs or as rows of numbers which scroll downward. Bar
graphs are shown by default.

The following commands are specific to the iostat(1) display; the
minimum unambiguous prefix may be supplied.

numbers Show the disk i/o statistics in numeric form. Values
are displayed in numeric columns which scroll
downward.

bars Show the disk i/o statistics in bar graph form
(default).

msps Toggle the display of average seek time (the default
is to not display seek times).

mbufs Display, in the lower window, the number of mbufs allocated
for particular uses, i.e. data, socket structures, etc.

vmstat Take over the entire display and show a (rather crowded)
compendium of statistics related to virtual memory usage,
process scheduling, device interrupts, system name
translation cacheing, disk i/o, etc.

The upper left quadrant of the screen shows the number of
users logged in and the load average over the last one,
five, and fifteen minute intervals. Below this line are
statistics on memory utilization. The first row of the
table reports memory usage only among active processes, that
is processes that have run in the previous twenty seconds.
The second row reports on memory usage of all processes.
The first column reports on the number of physical pages
claimed by processes. The second column reports the number
of physical pages that are devoted to read only text pages.
The third and fourth columns report the same two figures for
virtual pages, that is the number of pages that would be
needed if all processes had all of their pages. Finally the
last column shows the number of physical pages on the free
list.

Below the memory display is the disk usage display. It
reports the number of seeks, transfers, and number of
kilobyte blocks transferred per second averaged over the
refresh period of the display (by default, five seconds).
For some disks it also reports the average milliseconds per
seek. Note that the system only keeps statistics on at most
four disks.

Below the disk display is a list of the average number of
processes (over the last refresh interval) that are runnable
(‘r’), in page wait (‘p’), in disk wait other than paging
(‘d’), sleeping (‘s’), and swapped out but desiring to run
(‘w’). Below the queue length listing is a numerical
listing and a bar graph showing the amount of system (shown
as ‘=’), user (shown as ‘>’), nice (shown as ‘-’), and idle
time (shown as ‘ ’).

At the bottom left are statistics on name translations. It
lists the number of names translated in the previous
interval, the number and percentage of the translations that
were handled by the system wide name translation cache, and
the number and percentage of the translations that were
handled by the per process name translation cache.

Under the date in the upper right hand quadrant are
statistics on paging and swapping activity. The first two
columns report the average number of pages brought in and
out per second over the last refresh interval due to page
faults and the paging daemon. The third and fourth columns
report the average number of pages brought in and out per
second over the last refresh interval due to swap requests
initiated by the scheduler. The first row of the display
shows the average number of disk transfers per second over
the last refresh interval; the second row of the display
shows the average number of pages transferred per second
over the last refresh interval.

Below the paging statistics is a line listing the average
number of total reclaims (’Rec’), intransit blocking page
faults (‘It’), swap text pages found in free list (‘F/S’),
file system text pages found in free list (‘F/F’), reclaims
from free list (‘RFL’), pages freed by the clock daemon
(‘Fre’), and sequential process pages freed (‘SFr’) per
second over the refresh interval.

Below this line are statistics on the average number of zero
filled pages (‘zf’) and demand filled text pages (‘xf’) per
second over the refresh period. The first row indicates the
number of requests that were resolved, the second row shows
the number that were set up, and the last row shows the
percentage of setup requests were actually used. Note that
this percentage is usually less than 100%, however it may
exceed 100% if a large number of requests are actually used
long after they were set up during a period when no new
pages are being set up. Thus this figure is most
interesting when observed over a long time period, such as
from boot time (see below on getting such a display).

Below the page fill statistics is a column that lists the
average number of context switches (‘Csw’), traps (‘Trp’;
includes page faults), system calls (‘Sys’), interrupts
(‘Int’), characters output to DZ ports using pseudo-DMA
(‘Pdm’), network software interrupts (‘Sof’), page faults
(‘Flt’), pages scanned by the page daemon (‘Scn’), and
revolutions of the page daemon’s hand (‘Rev’) per second
over the refresh interval.

Running down the right hand side of the display is a
breakdown of the interrupts being handled by the system. At
the top of the list is the total interrupts per second over
the time interval. The rest of the column breaks down the
total on a device by device basis. Only devices that have
interrupted at least once since boot time are shown.

The following commands are specific to the vmstat(1) display; the
minimum unambiguous prefix may be supplied.

boot Display cumulative statistics since the system was
booted.

run Display statistics as a running total from the
point this command is given.

time Display statistics averaged over the refresh
interval (the default).

zero Reset running statistics to zero.

netstat
Display, in the lower window, network connections. By
default, network servers awaiting requests are not
displayed. Each address is displayed in the format
"host.port", with each shown symbolically, when possible.
It is possible to have addresses displayed numerically,
limit the display to a set of ports, hosts, and/or protocols
(the minimum unambiguous prefix may be supplied):

all Toggle the displaying of server processes
awaiting requests (this is the equivalent of
the -a flag to netstat(1)).

numbers Display network addresses numerically.

names Display network addresses symbolically.

protocol
Display only network connections using the indicated
protocol (currently either "tcp" or "udp").

ignore [ items ]
Do not display information about connections associated with
the specified hosts or ports. Hosts and ports may be
specified by name ("ucbmonet", "ftp"), or numerically.
Host addresses use the Internet dot notation
("128.32.0.9"). Multiple items may be specified with a
single command by separating them with spaces.

display [ items ]
Display information about the connections associated with
the specified hosts or ports. As for ignore, [ items ] may
be names or numbers.

show [ ports|hosts ]
Show, on the command line, the currently selected protocols,
hosts, and ports. Hosts and ports which are being ignored
are prefixed with a ‘!’. If ports or hosts is supplied as
an argument to show, then only the requested information
will be displayed.

reset Reset the port, host, and protocol matching mechanisms to
the default (any protocol, port, or host).

Commands to switch between displays may be abbreviated to the
minimum unambiguous prefix; for example, "io" for "iostat".
Certain information may be discarded when the screen size is
insufficient for display. For example, on a machine with 10 drives
the iostat(1) bar graph displays only 3 drives on a 24 line
terminal. When a bar graph would overflow the allotted screen
space it is truncated and the actual value is printed "over top"
of the bar.

The following commands are common to each display which shows
information about disk drives. These commands are used to select a
set of drives to report on, should your system have more drives
configured than can normally be displayed on the screen.

ignore [ drives ]
Do not display information about the drives indicated.
Multiple drives may be specified, separated by spaces.

display [ drives ]
Display information about the drives indicated. Multiple
drives may be specified, separated by spaces.

FILES
/vmunix for the namelist
/dev/kmem for information in main memory
/etc/hosts for host names
/etc/networks for network names
/etc/services for port names

AUTHOR
The unknown hacker. The pigs display is derived from a program of
the same name written by Bill Reeves.

HISTORY
appeared in 4.3 BSD.

BUGS
Takes 2-10 percent of the cpu. Certain displays presume a 24 line
by 80 character terminal. The swap space display should account
for space allocated to the user structure and page tables. The
vmstat display looks out of place because it is (it was added in as
a separate display rather than create a new program).

The whole thing is pretty hokey and was included in the
distribution under serious duress. Average seek time currently
unimplemented.