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TOP(1)			     General Commands Manual			  TOP(1)

NAME
     top - display and update information about the top cpu processes

SYNOPSIS
     top [ -SbiInqutv ] [ -dcount ] [ -stime ] [ -ofield ] [ -Uusername ] [ num-
     ber ]

DESCRIPTION
     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 capabili-
     ties and those that do not.  This distinction affects  the  choice  of  de-
     faults  for certain options.  In the remainder of this document, an "intel-
     ligent" 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.

OPTIONS
     -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 ig-
	    nored.  Interrupt characters (such as ^C and ^\) still have  an  ef-
	    fect.  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 expla-
	    nation  of	which keys perform what functions.  After the command is
	    processed, the screen will immediately be updated, even if the  com-
	    mand  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.

     -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 dis-
	    covering 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 names.

     -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 com-
	    mand "?".

     -dcount
	    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.

     -ofield
	    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.

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

     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 de-
     fault for count on an intelligent terminal is, in fact, infinity.

     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 sec-
     ond 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.

INTERACTIVE MODE
     When top is running in "interactive mode", it reads commands from the  ter-
     minal 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 rec-
     ognized, 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	informa-
	    tion is included in this display.

     q	    Quit top.

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

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

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

     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  fron  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 DISPLAY
     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, start-
     ing,  zombies,  and stopped), and a percentage of time spent in each of the
     processor states (user, nice, system, and idle).  It also includes informa-
     tion about physical and virtual memory allocation.

     The  remainder  of  the  screen  displays	information   about   individual
     processes.   This	display  is similar in spirit to ps(1) but it is not ex-
     actly 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  dis-
     played,  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 "<swapped>").

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

AUTHOR
     William LeFebvre, EECS Department, Northwestern University

ENVIRONMENT
     TOP  user-configurable defaults for options.

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

BUGS
     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 reality.

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

FreeBSD NOTES
DISPLAY OF THREADS
     The  '-H' option will toggle the display of kernel visible thread contexts.
     At runtime the 'H' key will toggle this mode. The default is OFF.

DESCRIPTION OF MEMORY
     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

     Active:
	    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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