SYSTAT(1)

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 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(8)), virtual memory statistics (a la vmstat(8)), 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:

-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.

^Z  Stop systat.

:   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''), in interrupt mode (``interrupt''), 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 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).

swap
    Show information about swap space usage on all the swap areas compiled into the kernel. The first column is the device name of the partition. The next column is the total space available in the partition. The Used column indicates the total blocks used so far; the graph shows the percentage of space in use on each partition. If there are more than one swap partition in use, a total line is also shown. Areas known to the kernel, but not in use are shown as not available.

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 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 `='), interrupt (shown as `+'), user (shown as `>'), nice (shown as `-'), and idle time (shown as ` ').

    Below the process display 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.

    At the bottom left 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 eight disks (this is controlled by the constant DK_NDRIVE in /sys/dkstat.h as a kernel compile-time constant).

    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 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 that 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 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 (``vangogh'', ``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 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
/kernel
    For the namelist.
/dev/kmem
    For information in main memory.
/dev/drum
    For information about swapped out processes.
/etc/hosts
    For host names.
/etc/networks
    For network names.
/etc/services
    For port names.

HISTORY
The systat program appeared in 4.3BSD.

BUGS
Takes 2-10 percent of the cpu. Certain displays presume a minimum of 80 characters per line. The vmstat display looks out of place because it is (it was added in as a separate display rather than created as a new program).