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SYSTAT(1)                    BSD Reference Manual                    SYSTAT(1)

     systat - display system statistics on a crt

     systat [-display] [refresh-interval]

     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 us-
     age, 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 in-
     terpreter 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 in-
                       terval 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 cur-
                 rent character erase, word erase, and line kill characters
                 may be used.

     The following commands are interpreted by the ``global'' command inter-

     help        Print the names of the available displays on the command

     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, numer-
                 ic, argument is provided it is interpreted as a refresh in-
                 terval (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 ac-
                 counted 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 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
                 msps        Toggle the display of average seek time (the de-
                             fault 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 avail-

     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) com-
                 pendium of statistics related to virtual memory usage, pro-
                 cess 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 re-
                 ports the number of seeks, transfers, and number of kilobyte
                 blocks transferred per second averaged over the refresh peri-
                 od 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 inter-
                 val, 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 statis-
                 tics 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 aver-
                 age 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

                 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 per-
                 centage of setup requests that were actually used.  Note that
                 this percentage is usually less than 100%, however it may ex-
                 ceed 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 av-
                 erage number of context switches (`Csw'), traps (`Trp'; in-
                 cludes 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 revo-
                 lutions of the page daemon's hand (`Rev') per second over the
                 refresh interval.

                 Running down the right hand side of the display is a break-
                 down 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 inter-
                 rupted 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 de-
                 fault, 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 unambigu-
                 ous 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 in-
                               dicated protocol (currently either ``tcp'' or
                 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
                               (``'').  Multiple items may be speci-
                               fied with a single command by separating them
                               with spaces.
                 display [items]
                               Display information about the connections asso-
                               ciated 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 se-
                               lected protocols, hosts, and ports.  Hosts and
                               ports which are being ignored are prefixed with
                               a `!'.  If ports or hosts is supplied as an ar-
                               gument to show, then only the requested infor-
                               mation 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 un-
     ambiguous prefix; for example, ``io'' for ``iostat''.  Certain informa-
     tion 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 nor-
     mally be displayed on the screen.

     ignore [drives]         Do not display information about the drives indi-
                             cated.  Multiple drives may be specified, sepa-
                             rated by spaces.
     display [drives]        Display information about the drives indicated.
                             Multiple drives may be specified, separated by

     /vmunix        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.

     The systat program appeared in 4.3BSD.

     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 pro-

4.3 Berkeley Distribution      December 30, 1993                             5