TOP(1) OpenBSD Reference Manual TOP(1)NAMEtop - display and update information about the top CPU processes
SYNOPSIStop [-1bCIinqSTu] [-d count] [-g string] [-o field] [-p pid] [-s time]
[-U user] [number]
DESCRIPTIONtop 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:
-1 Display CPU statistics on a single line instead of a line per
CPU.
-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 Show command line arguments as well as the process itself.
-d 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 to be shown before top
automatically exits. For intelligent terminals, no upper limit
is set. The default is 1 for dumb terminals.
-g string
Display only processes that contain string in their command name.
-I Do not display idle processes. By default, top displays both
active and idle processes.
-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.
-n Use non-interactive mode. This is identical to batch mode.
-o field
Sort the process display area using the specified field as the
primary key. The field name is the name of the column as seen in
the output, but in lower case. The OpenBSD version of top
supports cpu, size, res, time, pri, pid, and command.
-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. The value
may be fractional, to permit delays of less than 1 second. The
default delay between updates is 5 seconds.
-T Show process threads in the display. Normally, only the main
process is shown. This option makes all threads visible.
-U user
Show only those processes owned by user. This option currently
only accepts usernames and will not understand UID numbers.
-u Do not take the time to map UID numbers to usernames. Normally,
top will read as much of the password database 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.
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, 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, 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.
INTERACTIVE MODE
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(1)) are recognized, and a newline
terminates the input.
These commands are currently recognized (^L refers to control-L):
h | ? Display a summary of the commands (help screen).
^L Redraw the screen.
<space>
Update the screen.
q Quit top.
+ Reset any filters put in place by the `g', `p', and `u'
interactive commands, or their command line equivalents, or any
process highlighting put in place by the `P' interactive command.
1 Display CPU statistics on a single line instead of a line per
CPU.
C Toggle the display of process command line arguments.
d count
Show only count displays, then exit.
e Display a list of system errors (if any) generated by the last
kill or renice command.
g string
Display only processes that contain string in their command name.
`g+' shows all processes.
I | i Toggle the display of idle processes.
k [-sig] pid
Send signal -sig (TERM by default) to process pid. This acts
similarly to the command kill(1).
n|# count
Show count processes.
o field
Sort the process display area using the specified field as the
primary key. Values are the same as for the -o flag, as detailed
above.
P pid Highlight a specific process, selected by pid. `P+' removes
process highlighting.
p pid Show only the process pid. `p+' shows all processes.
r count pid
Change the priority (the nice) of a list of processes to count
for process pid. This acts similarly to the command renice(8).
S Toggle the display of system processes.
s time Set the delay between screen updates to time seconds.
T Toggle the display of process threads.
u user Show only those processes owned by user. `u+' shows processes
belonging to all users.
THE DISPLAY
The top few lines of the display show general information about the state
of the system, including the three load average numbers, the hostname,
the current time, the number of existing processes, the number of
processes in each state (starting, running, idle, stopped, zombie, dead,
and on processor), and a percentage of time spent in each of the
processor states (user, nice, system, interrupt, and idle). It also
includes information about physical and virtual memory allocation. The
load average numbers give the number of jobs in the run queue averaged
over 1, 5, and 15 minutes.
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 following fields are displayed:
PID The process ID.
USERNAME The name of the process's owner.
UID Used instead of USERNAME if -u is specified.
PRI The current priority of the process.
NICE The nice amount (in the range -20 to 20).
SIZE The total size of the process (the text, data, and stack
segments).
RES The current amount of resident memory.
STATE The current state (one of start, run, sleep, stop, idle,
zomb, dead, or onproc). On multiprocessor systems, this
is followed by a slash and the CPU number on which the
process is bound.
WAIT A description of the wait channel the process is sleeping
on if it's asleep.
TIME The number of system and user CPU seconds that the
process has used.
CPU The raw percentage of CPU usage and the default field on
which the display is sorted.
COMMAND The name of the command that the process is currently
running. (If the process is swapped out, this column is
enclosed by angle brackets.)
ENVIRONMENT
TOP User-configurable defaults for options.
FILES
/dev/kmem kernel memory
/dev/mem physical memory
/etc/passwd used to map user ID to user
/bsd kernel image
SEE ALSOfstat(1), kill(1), netstat(1), ps(1), stty(1), systat(1), mem(4),
iostat(8), pstat(8), renice(8), vmstat(8)AUTHORS
William LeFebvre, EECS Department, Northwestern University
BUGS
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.
OpenBSD 4.9 August 10, 2010 OpenBSD 4.9
