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TOP(1) FreeBSD General Commands Manual TOP(1)
NAME
top - display and update information about the top cpu processes
SYNOPSIS
top [-abCHIijnPpqSTtuvxz] [-d count] [-J jail] [-m mode] [-o field]
[-p pid] [-s time] [-U uid] [number]
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
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.
The options are as follows:
-a Display command names derived from the argv[] vector, rather than
real executable name. It it useful when you want to watch
applications, that puts their status information there. If the
real name differs from argv[0], it will be displayed in
parenthesis. Non-printable characters in the command line are
encoded in C-style backslash sequences or a three digit octal
sequences.
-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.
-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.
-d count
Show only count displays, then exit. A display is considered to
be one update of the screen. The default is 1 for dumb
terminals. Note that for count = 1 no information is available
about the percentage of time spent by the CPU in every state.
-H Display each thread for a multithreaded process individually. By
default a single summary line is displayed for each process.
-I Do not display idle processes. By default, top displays both
active and idle processes.
-J jail
Show only those processes owned by jail. This may be either the
jid or name of the jail. Use 0 to limit to host processes.
Using this option implies -j.
-j Display the jail(8) ID.
-m mode
Display statistics in the specified mode. Available modes are
cpu and io. Default is cpu.
-n Use "non-interactive" mode. This is identical to "batch" mode.
-o 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: "cpu", "size", "res", "time", "pri", "threads",
"total", "read", "write", "fault", "vcsw", "ivcsw", "jid",
"swap", or "pid".
-P Display per-cpu CPU usage statistics.
-p pid Show only the process pid.
-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.
-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.
-s time
Set the delay between screen updates to time seconds, which may
be fractional. The default delay between updates is 1 second.
-T Toggle displaying thread ID (tid) instead of process id (pid).
-t Do not display the top process itself.
-U username
Show only those processes owned by username. This option
currently only accepts usernames and will not understand uid
numbers.
-u Do not 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.
-w Display approximate swap usage for each process.
-z Do not display the system idle process.
Both count and number fields can be specified as "infinite", indicating
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(1)) are recognized, and a newline
terminates the input.
These commands are currently recognized (^L refers to control-L):
^L Redraw the screen.
h 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.
/ Display only processes that contain the specified string in their
command name. If displaying arguments is enabled, the arguments
are searched too. '+' shows all processes.
m Toggle the display between 'cpu' and 'io' modes.
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).
S Toggle the display of system processes.
a Toggle the display of process titles.
k Send a signal (SIGKILL 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 renice(8).
u Display only processes owned by a specific set of usernames
(prompt for username). If the username specified is simply "+"
or "-", then processes belonging to all users will be displayed.
Usernames can be added to and removed from the set by prepending
them with "+" and "-", respectively.
o Change the order in which the display is sorted. The sort key
names include "cpu", "res", "size", and "time." The default is
cpu.
i or I Toggle the display of idle processes.
j Toggle the display of jail(8) ID.
J Display only processes owned by a specific jail (prompt for
jail). If the jail specified is simply "+", then processes
belonging to all jails and the host will be displayed. This will
also enable the display of JID.
P Toggle the display of per-CPU statistics.
T Toggle display of TID and PID
t Toggle the display of the top process.
w Toggle the display of swap usage.
z Toggle the display of the system idle process.
THE DISPLAY
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 allocation.
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, JID, when displayed, is the
jail(8) ID corresponding to the process, 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(1) amount, SIZE is the total size of the process (text, data, and
stack), RES is the current amount of resident memory, SWAP is the
approximate amount of swap, if enabled (SIZE, RES and SWAP are given in
kilobytes), STATE is the current state (one of "START", "RUN" (shown as
"CPUn" on SMP systems), "SLEEP", "STOP", "ZOMB", "WAIT", "LOCK", or the
event on which the process waits), C is the processor number on which the
process is executing (visible only on SMP systems), 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 "<swapped>").
If a process is in the "SLEEP" or "LOCK" state, the state column will
report the name of the event or lock on which the process is waiting.
Lock names are prefixed with an asterisk "*" while sleep events are not.
DESCRIPTION OF MEMORY
Mem: 61M Active, 86M Inact, 368K Laundry, 22G Wired, 102G Free
ARC: 15G Total, 9303M MFU, 6155M MRU, 1464K Anon, 98M Header, 35M Other
15G Compressed, 27G Uncompressed, 1.75:1 Ratio, 174M Overhead
Swap: 4096M Total, 532M Free, 13% Inuse, 80K In, 104K Out
Free number of bytes free
ZFS ARC Stats
These stats are only displayed when the ARC is in use.
Total number of wired bytes used for the ZFS ARC
MRU number of ARC bytes holding most recently used data
MFU number of ARC bytes holding most frequently used data
Anon number of ARC bytes holding in flight data
Header number of ARC bytes holding headers
Other miscellaneous ARC bytes
Compressed bytes of memory used by ARC caches
Uncompressed bytes of data stored in ARC caches before compression
Ratio compression ratio of data cached in the ARC
Swap Stats
Total total available swap usage
Free total free swap usage
Inuse swap usage
In bytes paged in from swap devices (last interval)
Out bytes paged out to swap devices (last interval)
ENVIRONMENT
TOP Default set of arguments to top.
LC_CTYPE The locale to use when displaying the argv vector when -a
flag is specified.
SEE ALSO
kill(1), ps(1), stty(1), getrusage(2), humanize_number(3), mem(4),
renice(8)
AUTHORS
William LeFebvre, EECS Department, Northwestern University
BUGS
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.
FreeBSD 14.0-RELEASE-p11 November 18, 2021 FreeBSD 14.0-RELEASE-p11