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TOP(1)                  FreeBSD General Commands Manual                 TOP(1)

       top - display and update information about the top cpu processes

       top [ -bCHIinqStuv ] [ -dcount ] [ -mio|cpu ] [ -ofield ] [ -stime ] [
       -Uusername ] [ number ]

       Top displays the top processes on the system and periodically updates
       this information.  If standard output is an intelligent terminal (see
       below) then as many processes as will fit on the terminal screen are
       displayed by default.  Otherwise, a good number of them are shown
       (around 20).  Raw cpu percentage is used to rank the processes.  If
       number is given, then the top number processes will be displayed
       instead of the default.

       Top makes a distinction between terminals that support advanced
       capabilities and those that do not.  This distinction affects the
       choice of defaults for certain options.  In the remainder of this
       document, an "intelligent" terminal is one that supports cursor
       addressing, clear screen, and clear to end of line.  Conversely, a
       "dumb" terminal is one that does not support such features.  If the
       output of top is redirected to a file, it acts as if it were being run
       on a dumb terminal.

       -C     Toggle CPU display mode.  By default top displays the weighted
              CPU percentage in the WCPU column (this is the same value that
              ps(1) displays as CPU).  Each time -C flag is passed it toggles
              between "raw cpu" mode and "weighted cpu" mode, showing the
              "CPU" or the "WCPU" column respectively.

       -S     Show system processes in the display.  Normally, system
              processes such as the pager and the swapper are not shown.  This
              option makes them visible.

       -b     Use "batch" mode.  In this mode, all input from the terminal is
              ignored.  Interrupt characters (such as ^C and ^\) still have an
              effect.  This is the default on a dumb terminal, or when the
              output is not a terminal.

       -i     Use "interactive" mode.  In this mode, any input is immediately
              read for processing.  See the section on "Interactive Mode" for
              an explanation of which keys perform what functions.  After the
              command is processed, the screen will immediately be updated,
              even if the command was not understood.  This mode is the
              default when standard output is an intelligent terminal.

       -I     Do not display idle processes.  By default, top displays both
              active and idle processes.

       -t     Do not display the top process.

              Display either 'cpu' or 'io' statistics.  Default is 'cpu'.

       -n     Use "non-interactive" mode.  This is identical to "batch" mode.

       -q     Renice top to -20 so that it will run faster.  This can be used
              when the system is being very sluggish to improve the
              possibility of discovering the problem.  This option can only be
              used by root.

       -u     Do not take the time to map uid numbers to usernames.  Normally,
              top will read as much of the file "/etc/passwd" as is necessary
              to map all the user id numbers it encounters into login names.
              This option disables all that, while possibly decreasing
              execution time.  The uid numbers are displayed instead of the

       -v     Write version number information to stderr then exit
              immediately.  No other processing takes place when this option
              is used.  To see current revision information while top is
              running, use the help command "?".

              Show only count displays, then exit.  A display is considered to
              be one update of the screen.  This option allows the user to
              select the number of displays he wants to see before top
              automatically exits.  For intelligent terminals, no upper limit
              is set.  The default is 1 for dumb terminals.

       -stime Set the delay between screen updates to time seconds.  The
              default delay between updates is 2 seconds.

              Sort the process display area on the specified field.  The field
              name is the name of the column as seen in the output, but in
              lower case.  Likely values are "cpu", "size", "res", and "time",
              but may vary on different operating systems.  Note that not all
              operating systems support this option.

              Show only those processes owned by username.  This option
              currently only accepts usernames and will not understand uid

       Both count and number fields can be specified as "infinite", indicating
       that they can stretch as far as possible.  This is accomplished by
       using any proper prefix of the keywords "infinity", "maximum", or
       "all".  The default for count on an intelligent terminal is, in fact,

       The environment variable TOP is examined for options before the command
       line is scanned.  This enables a user to set his or her own defaults.
       The number of processes to display can also be specified in the
       environment variable TOP.  The options -I, -S, -u, and -t are actually
       toggles.  A second specification of any of these options will negate
       the first.  Thus a user who has the environment variable TOP set to
       "-I" may use the command "top -I" to see idle processes.

       When top is running in "interactive mode", it reads commands from the
       terminal and acts upon them accordingly.  In this mode, the terminal is
       put in "CBREAK", so that a character will be processed as soon as it is
       typed.  Almost always, a key will be pressed when top is between
       displays; that is, while it is waiting for time seconds to elapse.  If
       this is the case, the command will be processed and the display will be
       updated immediately thereafter (reflecting any changes that the command
       may have specified).  This happens even if the command was incorrect.
       If a key is pressed while top is in the middle of updating the display,
       it will finish the update and then process the command.  Some commands
       require additional information, and the user will be prompted
       accordingly.  While typing this information in, the user's erase and
       kill keys (as set up by the command stty) are recognized, and a newline
       terminates the input.

       These commands are currently recognized (^L refers to control-L):

       ^L     Redraw the screen.

       h or ? Display a summary of the commands (help screen).  Version
              information is included in this display.

       q      Quit top.

       d      Change the number of displays to show (prompt for new number).
              Remember that the next display counts as one, so typing d1 will
              make top show one final display and then immediately exit.

       m      Toggle the display between 'cpu' and 'io' modes.

       n or # Change the number of processes to display (prompt for new

       s      Change the number of seconds to delay between displays (prompt
              for new number).

       S      Toggle the display of system processes.

       k      Send a signal ("kill" by default) to a list of processes.  This
              acts similarly to the command kill(1)).

       r      Change the priority (the "nice") of a list of processes.  This
              acts similarly to the command renice(8)).

       u      Display only processes owned by a specific username (prompt for
              username).  If the username specified is simply "+", then
              processes belonging to all users will be displayed.

       o      Change the order in which the display is sorted.  This command
              is not available on all systems.  The sort key names vary from
              system to system but usually include:  "cpu", "res", "size",
              "time".  The default is cpu.

       e      Display a list of system errors (if any) generated by the last
              kill or renice command.

       i      (or I) Toggle the display of idle processes.

       t      Toggle the display of the top process.

       The actual display varies depending on the specific variant of Unix
       that the machine is running.  This description may not exactly match
       what is seen by top running on this particular machine.  Differences
       are listed at the end of this manual entry.

       The top few lines of the display show general information about the
       state of the system, including the last process id assigned to a
       process (on most systems), the three load averages, the current time,
       the number of existing processes, the number of processes in each state
       (sleeping, running, starting, zombies, and stopped), and a percentage
       of time spent in each of the processor states (user, nice, system, and
       idle).  It also includes information about physical and virtual memory

       The remainder of the screen displays information about individual
       processes.  This display is similar in spirit to ps(1) but it is not
       exactly the same.  PID is the process id, USERNAME is the name of the
       process's owner (if -u is specified, a UID column will be substituted
       for USERNAME), PRI is the current priority of the process, NICE is the
       nice amount (in the range -20 to 20), SIZE is the total size of the
       process (text, data, and stack), RES is the current amount of resident
       memory (both SIZE and RES are given in kilobytes), STATE is the current
       state (one of "sleep", "WAIT", "run", "idl", "zomb", or "stop"), TIME
       is the number of system and user cpu seconds that the process has used,
       WCPU, when displayed, is the weighted cpu percentage (this is the same
       value that ps(1) displays as CPU), CPU is the raw percentage and is the
       field that is sorted to determine the order of the processes, and
       COMMAND is the name of the command that the process is currently
       running (if the process is swapped out, this column is marked

       The "ABANDONED" state (known in the kernel as "SWAIT") was abandoned,
       thus the name.  A process should never end up in this state.

       William LeFebvre, EECS Department, Northwestern University

       TOP  user-configurable defaults for options.

       /dev/kmem      kernel memory
       /dev/mem       physical memory
       /etc/passwd         used to map uid numbers to user names
       /boot/kernel/kernel system image

       Don't shoot me, but the default for -I has changed once again.  So many
       people were confused by the fact that top wasn't showing them all the
       processes that I have decided to make the default behavior show idle
       processes, just like it did in version 2.  But to appease folks who
       can't stand that behavior, I have added the ability to set "default"
       options in the environment variable TOP (see the OPTIONS section).
       Those who want the behavior that version 3.0 had need only set the
       environment variable TOP to "-I".

       The command name for swapped processes should be tracked down, but this
       would make the program run slower.

       As with ps(1), things can change while top is collecting information
       for an update.  The picture it gives is only a close approximation to

       kill(1), ps(1), stty(1), mem(4), renice(8)

       The '-H' option will toggle the display of kernel visible thread
       contexts.  At runtime the 'H' key will toggle this mode. The default is

       Mem: 9220K Active, 1032K Inact, 3284K Wired, 1MB Cache, 2M Buf, 1320K
       Free Swap:   91M Total, 79M Free, 13% Inuse, 80K In, 104 K Out

       K: Kilobyte

       M:     Megabyte

       %:     1/100

              number of pages active

       Inact: number of pages inactive

       Wired: number of pages wired down, including cached file data pages

       Cache: number of pages used for VM-level disk caching

       Buf:   number of pages used for BIO-level disk caching

       Free:  number of pages free

       Total: total available swap usage

       Free:  total free swap usage

       Inuse: swap usage

       In:    pages paged in from swap devices (last interval)

       Out:   pages paged out to swap devices (last interval)

4th Berkeley Distribution            Local                              TOP(1)


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