xref: /freebsd/usr.bin/top/top.1 (revision 0bf48626aaa33768078f5872b922b1487b3a9296)
1.\" $FreeBSD$
2.Dd October 2, 2018
3.Dt TOP 1
4.Os
5.Sh NAME
6.Nm top
7.Nd display and update information about the top cpu processes
8.Sh SYNOPSIS
9.Nm
10.Op Fl CHIPSTabijnpqtuvxz
11.Op Fl J Ar jail
12.Op Fl U Ar uid
13.Op Fl d Ar count
14.Op Fl m Ar cpu|io
15.Op Fl s Ar time
16.Op Fl o Ar field
17.Op Fl p Ar pid
18.Op Ar count
19.Sh DESCRIPTION
20.Nm
21displays the top
22processes on the system and periodically updates this information.
23If standard output is an intelligent terminal (see below) then
24as many processes as will fit on the terminal screen are displayed
25by default.
26Otherwise, a good number of them are shown (around 20).
27Raw cpu percentage is used to rank the processes.
28If
29.Ar number
30is given, then the top
31.Ar number
32processes will be displayed instead of the default.
33.Pp
34.Nm
35makes a distinction between terminals that support advanced capabilities
36and those that do not.
37This distinction affects the choice of defaults for certain options.
38In the remainder of this document, an \*(lqintelligent\*(rq terminal is one that
39supports cursor addressing, clear screen, and clear to end of line.
40Conversely, a \*(lqdumb\*(rq terminal is one that does not support such
41features.
42If the output of
43.Nm
44is redirected to a file, it acts as if it were being run on a dumb
45terminal.
46.Bl -tag -width indent -compact
47.It Fl C
48Toggle CPU display mode.
49By default top displays the weighted CPU percentage in the WCPU column
50(this is the same value that
51.Xr ps 1
52displays as CPU).
53Each time
54.Fl C
55flag is passed it toggles between \*(lqraw cpu\*(rq mode
56and \*(lqweighted cpu\*(rq mode, showing the \*(lqCPU\*(rq or
57the \*(lqWCPU\*(rq column respectively.
58.It Fl S
59Show system processes in the display.
60Normally, system processes such as the pager and the swapper are not shown.
61This option makes them visible.
62.It Fl a
63Display command names derived from the argv[] vector, rather than real
64executable name.
65It it useful when you want to watch applications, that
66puts their status information there.
67If the real name differs from argv[0],
68it will be displayed in parenthesis.
69.It Fl b
70Use \*(lqbatch\*(rq mode.
71In this mode, all input from the terminal is
72ignored.
73Interrupt characters (such as ^C and ^\e) still have an effect.
74This is the default on a dumb terminal, or when the output is not a terminal.
75.It Fl H
76Display each thread for a multithreaded process individually.
77By default a single summary line is displayed for each process.
78.It Fl i
79Use \*(lqinteractive\*(rq mode.
80In this mode, any input is immediately
81read for processing.
82See the section on \*(lqInteractive Mode\*(rq
83for an explanation of
84which keys perform what functions.
85After the command is processed, the
86screen will immediately be updated, even if the command was not
87understood.
88This mode is the default when standard output is an
89intelligent terminal.
90.It Fl I
91Do not display idle processes.
92By default, top displays both active and idle processes.
93.It Fl j
94Display the
95.Xr jail 8
96ID.
97.It Fl T
98Toggle displaying thread ID (tid) instead of process id (pid).
99.It Fl t
100Do not display the
101.Nm
102process itself.
103.It Fl display
104Display either 'cpu' or 'io' statistics.
105Default is 'cpu'.
106.It Fl n
107Use \*(lqnon-interactive\*(rq mode.
108This is identical to \*(lqbatch\*(rq
109mode.
110.It Fl P
111Display per-cpu CPU usage statistics.
112.It Fl q
113Renice
114.Nm
115to -20 so that it will run faster.
116This can be used when the system is
117being very sluggish to improve the possibility of discovering the problem.
118This option can only be used by root.
119.It Fl u
120Do not map uid numbers to usernames.
121Normally,
122.Nm
123will read as much of the file \*(lq/etc/passwd\*(rq as is necessary to map
124all the user id numbers it encounters into login names.
125This option disables all that, while possibly decreasing execution time.
126The uid numbers are displayed instead of the names.
127.It Fl v
128Write version number information to stderr then exit immediately.
129.It Fl w
130Display approximate swap usage for each process.
131.It Fl z
132Do not display the system idle process.
133.It Fl d Ar count
134Show only
135.Ar count
136displays, then exit.
137A display is considered to be one update of the
138screen.
139The default is 1 for dumb terminals.
140Note that for
141.Ar count
142= 1
143no information is available about the percentage of time spent by the CPU in every state.
144.It Fl s Ar time
145Set the delay between screen updates to
146.Ar time
147seconds.
148The default delay between updates is 1 second.
149.It Fl o Ar field
150Sort the process display area on the specified field.
151The field name
152is the name of the column as seen in the output, but in lower case:
153\*(lqcpu\*(lq, \*(rqsize\*(lq, \*(rqres\*(lq, \*(rqtime\*(lq,
154\*(rqpri\*(lq, \*(rqthreads\*(lq, \*(lqtotal\*(lq, \*(rqread\*(lq,
155\*(rqwrite\*(lq, \*(rqfault\*(lq, \*(rqvcsw\*(lq, \*(rqivcsw\*(lq,
156\*(lqjid\*(lq, \*(rqswap\*(lq or \*(rqpid\*(lq.
157.It Fl p Ar pid
158Show only the process
159.Ar pid .
160.It Fl J Ar jail
161Show only those processes owned by
162.Ar jail .
163This may be either the
164.Ar jid
165or
166.Ar name
167of the jail.
168Use
1690
170to limit to host processes.
171Using this option implies
172.Fl j .
173.Pp
174.It Fl U Ar username
175Show only those processes owned by
176.Ar username .
177This option currently only accepts usernames and will not understand
178uid numbers.
179.El
180.Pp
181Both
182.Ar count
183and
184.Ar number
185fields can be specified as \*(lqinfinite\*(rq, indicating that they can
186stretch as far as possible.
187This is accomplished by using any proper
188prefix of the keywords
189\*(lqinfinity\*(rq,
190\*(lqmaximum\*(rq,
191or
192\*(lqall\*(rq.
193Boolean flags are toggles.
194A second specification of any of these options will negate the first.
195.Sh "INTERACTIVE MODE"
196When
197.Nm
198is running in \*(lqinteractive mode\*(rq, it reads commands from the
199terminal and acts upon them accordingly.
200In this mode, the terminal is
201put in \*(lqCBREAK\*(rq, so that a character will be
202processed as soon as it is typed.
203Almost always, a key will be
204pressed when
205.Nm
206is between displays; that is, while it is waiting for
207.Ar time
208seconds to elapse.
209If this is the case, the command will be
210processed and the display will be updated immediately thereafter
211(reflecting any changes that the command may have specified).
212This
213happens even if the command was incorrect.
214If a key is pressed while
215.Nm
216is in the middle of updating the display, it will finish the update and
217then process the command.
218Some commands require additional information,
219and the user will be prompted accordingly.
220While typing this information
221in, the user's erase and kill keys (as set up by the command
222.Xr stty 1 )
223are recognized, and a newline terminates the input.
224.Pp
225These commands are currently recognized (^L refers to control-L):
226.Bl -tag -width indent
227.It ^L
228Redraw the screen.
229.It h
230Display a summary of the commands (help screen).
231Version information
232is included in this display.
233.It q
234Quit
235.Nm
236.It d
237Change the number of displays to show (prompt for new number).
238Remember that the next display counts as one, so typing
239.It d1
240will make
241.Nm
242show one final display and then immediately exit.
243.It m
244Toggle the display between 'cpu' and 'io' modes.
245.It n or #
246Change the number of processes to display (prompt for new number).
247.It s
248Change the number of seconds to delay between displays
249(prompt for new number).
250.It S
251Toggle the display of system processes.
252.It a
253Toggle the display of process titles.
254.It k
255Send a signal (\*(lqkill\*(rq by default) to a list of processes.
256This acts similarly to the command
257.Xr kill 1 .
258.It r
259Change the priority (the \*(lqnice\*(rq) of a list of processes.
260This acts similarly to
261.Xr renice 8 .
262.It u
263Display only processes owned by a specific set of usernames (prompt for
264username).
265If the username specified is simply \*(lq+\*(rq or \*(lq-\*(rq,
266then processes belonging to all users will be displayed.
267Usernames can be added
268to and removed from the set by prepending them with \*(lq+\*(rq and
269\*(lq-\*(rq, respectively.
270.It o
271Change the order in which the display is sorted.
272The sort key names include
273\*(lqcpu\*(rq, \*(lqres\*(rq, \*(lqsize\*(rq,
274\*(lqtime\*(rq.
275The default is cpu.
276.It p
277Display a specific process (prompt for pid).
278If the pid specified is simply \*(lq+\*(rq, then show all processes.
279.It e
280Display a list of system errors (if any) generated by the last
281command.
282.It B H
283Toggle the display of threads.
284.It i or I
285Toggle the display of idle processes.
286.It j
287Toggle the display of
288.Xr jail 8
289ID.
290.It J
291Display only processes owned by a specific jail (prompt for jail).
292If the jail specified is simply \*(lq+\*(rq, then processes belonging
293to all jails and the host will be displayed.
294This will also enable the display of JID.
295.It P
296Toggle the display of per-CPU statistics.
297.It T
298Toggle display of TID and PID
299.It t
300Toggle the display of the
301.Nm
302process.
303.It w
304Toggle the display of swap usage.
305.It z
306Toggle the display of the system idle process.
307.El
308.Sh "THE DISPLAY"
309The top few lines of the display show general information
310about the state of the system, including
311the last process id assigned to a process (on most systems),
312the three load averages,
313the current time,
314the number of existing processes,
315the number of processes in each state
316(sleeping, running, starting, zombies, and stopped),
317and a percentage of time spent in each of the processor states
318(user, nice, system, and idle).
319It also includes information about physical and virtual memory allocation.
320.Pp
321The remainder of the screen displays information about individual
322processes.
323This display is similar in spirit to
324.Xr ps 1
325but it is not exactly the same.
326PID is the process id,
327JID, when displayed, is the
328.Xr jail 8
329ID corresponding to the process,
330USERNAME is the name of the process's owner (if
331.Fl u
332is specified, a UID column will be substituted for USERNAME),
333PRI is the current priority of the process,
334NICE is the
335.Xr nice 1
336amount,
337SIZE is the total size of the process (text, data, and stack),
338RES is the current amount of resident memory,
339SWAP is the approximate amount of swap, if enabled
340(SIZE, RES and SWAP are given in kilobytes),
341STATE is the current state (one of \*(lqSTART\*(rq, \*(lqRUN\*(rq
342(shown as \*(lqCPUn\*(rq on SMP systems), \*(lqSLEEP\*(rq, \*(lqSTOP\*(rq,
343\*(lqZOMB\*(rq, \*(lqWAIT\*(rq, \*(lqLOCK\*(rq or the event on which the
344process waits),
345C is the processor number on which the process is executing
346(visible only on SMP systems),
347TIME is the number of system and user cpu seconds that the process has used,
348WCPU, when displayed, is the weighted cpu percentage (this is the same
349value that
350.Xr ps 1
351displays as CPU),
352CPU is the raw percentage and is the field that is sorted to determine
353the order of the processes, and
354COMMAND is the name of the command that the process is currently running
355(if the process is swapped out, this column is marked \*(lq<swapped>\*(rq).
356.Pp
357If a process is in the \*(lqSLEEP\*(rq or \*(lqLOCK\*(rq state,
358the state column will report the name of the event or lock on which the
359process is waiting.
360Lock names are prefixed with an asterisk \*(lq*\*(rq while sleep events
361are not.
362.Sh DESCRIPTION OF MEMORY
363.Bd -literal
364Mem: 61M Active, 86M Inact, 368K Laundry, 22G Wired, 102G Free
365ARC: 15G Total, 9303M MFU, 6155M MRU, 1464K Anon, 98M Header, 35M Other
366     15G Compressed, 27G Uncompressed, 1.75:1 Ratio, 174M Overhead
367Swap: 4096M Total, 532M Free, 13% Inuse, 80K In, 104K Out
368.Ed
369.Ss Physical Memory Stats
370.Bl -tag -width "Uncompressed" -compact
371.It Em Active
372number of bytes active
373.It Em Inact
374number of clean bytes inactive
375.It Em Laundry
376number of dirty bytes queued for laundering
377.It Em Wired
378number of bytes wired down, including IO-level cached file data pages
379.It Em Buf
380number of bytes used for IO-level disk caching
381.It Em Free
382number of bytes free
383.El
384.Ss ZFS ARC Stats
385These stats are only displayed when the ARC is in use.
386.Pp
387.Bl -tag -width "Uncompressed" -compact
388.It Em Total
389number of wired bytes used for the ZFS ARC
390.It Em MRU
391number of ARC bytes holding most recently used data
392.It Em MFU
393number of ARC bytes holding most frequently used data
394.It Em Anon
395number of ARC bytes holding in flight data
396.It Em Header
397number of ARC bytes holding headers
398.It Em Other
399miscellaneous ARC bytes
400.It Em Compressed
401bytes of memory used by ARC caches
402.It Em Uncompressed
403bytes of data stored in ARC caches before compression
404.It Em Ratio
405compression ratio of data cached in the ARC
406.El
407.Ss Swap Stats
408.Bl -tag -width "Uncompressed" -compact
409.It Em Total
410total available swap usage
411.It Em Free
412total free swap usage
413.It Em Inuse
414swap usage
415.It Em \&In
416bytes paged in from swap devices (last interval)
417.It Em Out
418bytes paged out to swap devices (last interval)
419.El
420.Sh ENVIRONMENT
421.Bl -tag -width "Uncompressed"
422.It Ev TOP
423Default set of arguments to
424.Nm .
425.El
426.Sh SEE ALSO
427.Xr kill 1 ,
428.Xr ps 1 ,
429.Xr stty 1 ,
430.Xr getrusage 2 ,
431.Xr humanize_number 3 ,
432.Xr mem 4 ,
433.Xr renice 8
434.Sh AUTHORS
435.An William LeFebvre, EECS Department, Northwestern University
436.Sh BUGS
437The command name for swapped processes should be tracked down, but this
438would make the program run slower.
439.Pp
440As with
441.Xr ps 1 ,
442things can change while
443.Nm
444is collecting information for an update.
445The picture it gives is only a close approximation to reality.
446