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TOP(1)                      General Commands Manual                     TOP(1)

       top - display and update information about the top cpu processes

       top [ -1CISTabcinqtuv ] [ -dcount ] [ -mmode ] [ -ofield ] [ -ppid ] [
       -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.

       -1, --percpustates
              Display per-cpu states on a multi-processor machine.

       -C, --color
              Turn off the use of color in the display.

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

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

       -T, --tag-names
              List all available color tags and the current set of tests used
              for color highlighting, then exit.

       -a, --all
              Show all processes for as long as possible.  This is shorthand
              for "-d all all".  This option is especially handy in batch

       -b, -n, --batch
              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.

       -c, --full-commands
              Show the full command line for each process. Default is to show
              just the command name.  This option is not supported on all

       -i, --interactive
              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.

       -q, --quick
              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.

       -t, --threads
              Show individual threads on separate lines.  By default, on
              systems which support threading, each process is shown with a
              count of the number of threads. This option shows each thread on
              a separate line.  This option is not supported on all platforms.

       -u, --uids
              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, --version
              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 "?".

       -d count, --displays count
              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.  Any proper prefix of the words "infinity",
              "maximum", or "all" can be used to indicate an infinite number
              of displays.  The default for intelligent terminals is infinity.
              The default for dumb terminals is 1.

       -m mode, --mode=mode
              Start the display in an alternate mode.  Some platforms support
              multiple process displays to show additional process
              information.  The value mode is a number indicating which mode
              to display.  The default is 0.  On platforms that do not have
              multiple display modes this option has no effect.

       -o field, --sort-order=field
              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.

       -p pid, --pid=pid
              Only display the specified pid.

       -s time, --delay=time
              Set the delay between screen updates to time seconds.  The
              default delay between updates is 5 seconds.

       -U username, --user=username
              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 -C, -I, -S, and -u 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.  Note that a control-L (^L) always redraws the
       current screen and a space forces an immediate update to the screen
       using new data.

       These commands are currently recognized:

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

       1      Toggle the display of per-cpu states.

       C      Toggle the use of color in the display.

       c      Display only processes whose commands match the specified
              string.  An empty string will display all processes.  This
              command is not supported on all platforms.

       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.

       f      Toggle the display of the full command line.

       H      Toggle the display of threads on separate lines.  By default, on
              systems which support threading, each process is shown with a
              count of the number of threads. This command shows each thread
              on a separate line.  This command is not supported on all

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

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

       M      Sort display by memory usage.  Shorthand for "o size".

       m      Change to a different process display mode.  Some systems
              provide multiple display modes for the process display which
              shows different information.  This command toggles between the
              available modes.  This command is not supported on all

       N      Sort by process id.  Shorthand for "o pid".

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

       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.

       P      Sort by CPU usage.  Shorthand for "o cpu".

       p      Display only process with the specified pid (prompt for process
              id).  If the pid specified is simply "-1", then all processes
              are displayed.

       q      Quit top.

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

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

       T      Sort by CPU time.  Shorthand for "o time".

       U      Toggle between displaying usernames and uids.

       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.

       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 lines of the display show general information about the state
       of the system.  The first line shows (on some systems) the last process
       id assigned to a process, the three load averages, the system uptime,
       and the current time.  The second line displays the total number of
       processes followed by a breakdown of processes per state.  Examples of
       states common to Unix systems are sleeping, running, starting, stopped,
       and zombie.  The next line displays a percentage of time spent in each
       of the processor states (typically user, nice, system, idle, and
       iowait).  These percentages show the processor activity during the time
       since the last update.  For multi-processor systems, this information
       is a summation of time across all processors.  The next line shows
       kernel-related activity (not available on all systems).  The numbers
       shown on this line are per-second rates sampled since the last update.
       The exact information displayed varies between systems, but some
       examples are: context switches, interrupts, traps, forks, and page
       faults.  The last one or two lines show a summary of memory and swap
       activity.  These lines vary between systems.

       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.  The columns displayed by top will differ slightly
       between operating systems.  Generally, the following fields are

       PID    The process id.

              Username of the process's owner (if -u is specified, a UID
              column will be substituted for USERNAME).

       THR    The number of threads in the processes (this column may also be
              labeled NLWP).

       PRI    Current priority of the process.

       NICE   Nice amount in the range -20 to 20, as established by the use of
              the command nice.

       SIZE   Total size of the process (text, data, and stack) given in

       RES    Resident memory: current amount of process memory that resides
              in physical memory, given in kilobytes.

       STATE  Current state (typically one of "sleep", "run", "idl", "zomb",
              or "stop").

       TIME   Number of system and user cpu seconds that the process has used.

       WCPU   Weighted percentage of available cpu time used by this process.

       CPU    Percentage of available cpu time used by this process.

              Name of the command that the process is currently running.

       Top supports the use of ANSI color in its output. By default, color is
       available but not used.  The environment variable TOPCOLORS specifies
       colors to use and conditions for which they should be used.  At the
       present time, only numbers in the summary display area can be colored.
       In a future version it will be possible to highlight numbers in the
       process display area as well.  The environment variable is the only way
       to specify color: there is no equivalent command line option.  Note
       that the environment variable TOPCOLOURS is also understood. The
       British spelling takes precedence.  The use of color only works on
       terminals that understand and process ANSI color escape sequences.

       The environment variable is a sequence of color specifications,
       separated by colons. Each specification takes the form tag=min,max#code
       where tag is the name of the value to check, min and max specify a
       range for the value, and code is an ANSI color code.  Multiple color
       codes can be listed and separated with semi-colons.  A missing min
       implies the lowest possible value (usually 0) and a missing max implies
       infinity. The comma must always be present. When specifying numbers for
       load averages, they should be multiplied by 100.  For example, the
       specification 1min=500,1000#31 indicates that a 1 minute load average
       between 5 and 10 should be displayed in red. Color attributes can be
       combined.  For example, the specification 5min=1000,#37;41 indicates
       that a 5 minute load average higher than 10 should be displayed with
       white characters on a red background. A special tag named header is
       used to control the color of the header for process display.  It should
       be specified with no lower and upper limits, specifically header=,#
       followed by the ANSI color code.

       You can see a list of color codes recognized by this installation of
       top with the -T option.  This will also show the current set of tests
       used for color highlighting, as specified in the environment.

       William LeFebvre

       TOP       user-configurable defaults for options.  TOPCOLORS     color

       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)

       Copyright (C) 1984-2007 William LeFebvre. For additional licensing
       information, see http://www.unixtop.org/license/

4th Berkeley Distribution      November 5, 2018                         TOP(1)