xref: /freebsd/usr.bin/top/top.1 (revision ecc2b89f96e1afd53c53d2dbf05aaa4bad7fe171)
1.\" $FreeBSD$
2.Dd September 21, 2019
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.
69Non-printable characters in the command line are
70encoded in C-style backslash sequences or
71a three digit octal sequences.
72.It Fl b
73Use \*(lqbatch\*(rq mode.
74In this mode, all input from the terminal is
75ignored.
76Interrupt characters (such as ^C and ^\e) still have an effect.
77This is the default on a dumb terminal, or when the output is not a terminal.
78.It Fl H
79Display each thread for a multithreaded process individually.
80By default a single summary line is displayed for each process.
81.It Fl i
82Use \*(lqinteractive\*(rq mode.
83In this mode, any input is immediately
84read for processing.
85See the section on \*(lqInteractive Mode\*(rq
86for an explanation of
87which keys perform what functions.
88After the command is processed, the
89screen will immediately be updated, even if the command was not
90understood.
91This mode is the default when standard output is an
92intelligent terminal.
93.It Fl I
94Do not display idle processes.
95By default, top displays both active and idle processes.
96.It Fl j
97Display the
98.Xr jail 8
99ID.
100.It Fl T
101Toggle displaying thread ID (tid) instead of process id (pid).
102.It Fl t
103Do not display the
104.Nm
105process itself.
106.It Fl display
107Display either 'cpu' or 'io' statistics.
108Default is 'cpu'.
109.It Fl n
110Use \*(lqnon-interactive\*(rq mode.
111This is identical to \*(lqbatch\*(rq
112mode.
113.It Fl P
114Display per-cpu CPU usage statistics.
115.It Fl q
116Renice
117.Nm
118to -20 so that it will run faster.
119This can be used when the system is
120being very sluggish to improve the possibility of discovering the problem.
121This option can only be used by root.
122.It Fl u
123Do not map uid numbers to usernames.
124Normally,
125.Nm
126will read as much of the file \*(lq/etc/passwd\*(rq as is necessary to map
127all the user id numbers it encounters into login names.
128This option disables all that, while possibly decreasing execution time.
129The uid numbers are displayed instead of the names.
130.It Fl v
131Write version number information to stderr then exit immediately.
132.It Fl w
133Display approximate swap usage for each process.
134.It Fl z
135Do not display the system idle process.
136.It Fl d Ar count
137Show only
138.Ar count
139displays, then exit.
140A display is considered to be one update of the
141screen.
142The default is 1 for dumb terminals.
143Note that for
144.Ar count
145= 1
146no information is available about the percentage of time spent by the CPU in every state.
147.It Fl s Ar time
148Set the delay between screen updates to
149.Ar time
150seconds.
151The default delay between updates is 1 second.
152.It Fl o Ar field
153Sort the process display area on the specified field.
154The field name
155is the name of the column as seen in the output, but in lower case:
156\*(lqcpu\*(lq, \*(rqsize\*(lq, \*(rqres\*(lq, \*(rqtime\*(lq,
157\*(rqpri\*(lq, \*(rqthreads\*(lq, \*(lqtotal\*(lq, \*(rqread\*(lq,
158\*(rqwrite\*(lq, \*(rqfault\*(lq, \*(rqvcsw\*(lq, \*(rqivcsw\*(lq,
159\*(lqjid\*(lq, \*(rqswap\*(lq or \*(rqpid\*(lq.
160.It Fl p Ar pid
161Show only the process
162.Ar pid .
163.It Fl J Ar jail
164Show only those processes owned by
165.Ar jail .
166This may be either the
167.Ar jid
168or
169.Ar name
170of the jail.
171Use
1720
173to limit to host processes.
174Using this option implies
175.Fl j .
176.Pp
177.It Fl U Ar username
178Show only those processes owned by
179.Ar username .
180This option currently only accepts usernames and will not understand
181uid numbers.
182.El
183.Pp
184Both
185.Ar count
186and
187.Ar number
188fields can be specified as \*(lqinfinite\*(rq, indicating that they can
189stretch as far as possible.
190This is accomplished by using any proper
191prefix of the keywords
192\*(lqinfinity\*(rq,
193\*(lqmaximum\*(rq,
194or
195\*(lqall\*(rq.
196Boolean flags are toggles.
197A second specification of any of these options will negate the first.
198.Sh "INTERACTIVE MODE"
199When
200.Nm
201is running in \*(lqinteractive mode\*(rq, it reads commands from the
202terminal and acts upon them accordingly.
203In this mode, the terminal is
204put in \*(lqCBREAK\*(rq, so that a character will be
205processed as soon as it is typed.
206Almost always, a key will be
207pressed when
208.Nm
209is between displays; that is, while it is waiting for
210.Ar time
211seconds to elapse.
212If this is the case, the command will be
213processed and the display will be updated immediately thereafter
214(reflecting any changes that the command may have specified).
215This
216happens even if the command was incorrect.
217If a key is pressed while
218.Nm
219is in the middle of updating the display, it will finish the update and
220then process the command.
221Some commands require additional information,
222and the user will be prompted accordingly.
223While typing this information
224in, the user's erase and kill keys (as set up by the command
225.Xr stty 1 )
226are recognized, and a newline terminates the input.
227.Pp
228These commands are currently recognized (^L refers to control-L):
229.Bl -tag -width indent
230.It ^L
231Redraw the screen.
232.It h
233Display a summary of the commands (help screen).
234Version information
235is included in this display.
236.It q
237Quit
238.Nm
239.It d
240Change the number of displays to show (prompt for new number).
241Remember that the next display counts as one, so typing
242.It d1
243will make
244.Nm
245show one final display and then immediately exit.
246.It m
247Toggle the display between 'cpu' and 'io' modes.
248.It n or #
249Change the number of processes to display (prompt for new number).
250.It s
251Change the number of seconds to delay between displays
252(prompt for new number).
253.It S
254Toggle the display of system processes.
255.It a
256Toggle the display of process titles.
257.It k
258Send a signal (\*(lqkill\*(rq by default) to a list of processes.
259This acts similarly to the command
260.Xr kill 1 .
261.It r
262Change the priority (the \*(lqnice\*(rq) of a list of processes.
263This acts similarly to
264.Xr renice 8 .
265.It u
266Display only processes owned by a specific set of usernames (prompt for
267username).
268If the username specified is simply \*(lq+\*(rq or \*(lq-\*(rq,
269then processes belonging to all users will be displayed.
270Usernames can be added
271to and removed from the set by prepending them with \*(lq+\*(rq and
272\*(lq-\*(rq, respectively.
273.It o
274Change the order in which the display is sorted.
275The sort key names include
276\*(lqcpu\*(rq, \*(lqres\*(rq, \*(lqsize\*(rq,
277\*(lqtime\*(rq.
278The default is cpu.
279.It p
280Display a specific process (prompt for pid).
281If the pid specified is simply \*(lq+\*(rq, then show all processes.
282.It e
283Display a list of system errors (if any) generated by the last
284command.
285.It B H
286Toggle the display of threads.
287.It i or I
288Toggle the display of idle processes.
289.It j
290Toggle the display of
291.Xr jail 8
292ID.
293.It J
294Display only processes owned by a specific jail (prompt for jail).
295If the jail specified is simply \*(lq+\*(rq, then processes belonging
296to all jails and the host will be displayed.
297This will also enable the display of JID.
298.It P
299Toggle the display of per-CPU statistics.
300.It T
301Toggle display of TID and PID
302.It t
303Toggle the display of the
304.Nm
305process.
306.It w
307Toggle the display of swap usage.
308.It z
309Toggle the display of the system idle process.
310.El
311.Sh "THE DISPLAY"
312The top few lines of the display show general information
313about the state of the system, including
314the last process id assigned to a process (on most systems),
315the three load averages,
316the current time,
317the number of existing processes,
318the number of processes in each state
319(sleeping, running, starting, zombies, and stopped),
320and a percentage of time spent in each of the processor states
321(user, nice, system, and idle).
322It also includes information about physical and virtual memory allocation.
323.Pp
324The remainder of the screen displays information about individual
325processes.
326This display is similar in spirit to
327.Xr ps 1
328but it is not exactly the same.
329PID is the process id,
330JID, when displayed, is the
331.Xr jail 8
332ID corresponding to the process,
333USERNAME is the name of the process's owner (if
334.Fl u
335is specified, a UID column will be substituted for USERNAME),
336PRI is the current priority of the process,
337NICE is the
338.Xr nice 1
339amount,
340SIZE is the total size of the process (text, data, and stack),
341RES is the current amount of resident memory,
342SWAP is the approximate amount of swap, if enabled
343(SIZE, RES and SWAP are given in kilobytes),
344STATE is the current state (one of \*(lqSTART\*(rq, \*(lqRUN\*(rq
345(shown as \*(lqCPUn\*(rq on SMP systems), \*(lqSLEEP\*(rq, \*(lqSTOP\*(rq,
346\*(lqZOMB\*(rq, \*(lqWAIT\*(rq, \*(lqLOCK\*(rq or the event on which the
347process waits),
348C is the processor number on which the process is executing
349(visible only on SMP systems),
350TIME is the number of system and user cpu seconds that the process has used,
351WCPU, when displayed, is the weighted cpu percentage (this is the same
352value that
353.Xr ps 1
354displays as CPU),
355CPU is the raw percentage and is the field that is sorted to determine
356the order of the processes, and
357COMMAND is the name of the command that the process is currently running
358(if the process is swapped out, this column is marked \*(lq<swapped>\*(rq).
359.Pp
360If a process is in the \*(lqSLEEP\*(rq or \*(lqLOCK\*(rq state,
361the state column will report the name of the event or lock on which the
362process is waiting.
363Lock names are prefixed with an asterisk \*(lq*\*(rq while sleep events
364are not.
365.Sh DESCRIPTION OF MEMORY
366.Bd -literal
367Mem: 61M Active, 86M Inact, 368K Laundry, 22G Wired, 102G Free
368ARC: 15G Total, 9303M MFU, 6155M MRU, 1464K Anon, 98M Header, 35M Other
369     15G Compressed, 27G Uncompressed, 1.75:1 Ratio, 174M Overhead
370Swap: 4096M Total, 532M Free, 13% Inuse, 80K In, 104K Out
371.Ed
372.Ss Physical Memory Stats
373.Bl -tag -width "Uncompressed" -compact
374.It Em Active
375number of bytes active
376.It Em Inact
377number of clean bytes inactive
378.It Em Laundry
379number of dirty bytes queued for laundering
380.It Em Wired
381number of bytes wired down, including IO-level cached file data pages
382.It Em Buf
383number of bytes used for IO-level disk caching
384.It Em Free
385number of bytes free
386.El
387.Ss ZFS ARC Stats
388These stats are only displayed when the ARC is in use.
389.Pp
390.Bl -tag -width "Uncompressed" -compact
391.It Em Total
392number of wired bytes used for the ZFS ARC
393.It Em MRU
394number of ARC bytes holding most recently used data
395.It Em MFU
396number of ARC bytes holding most frequently used data
397.It Em Anon
398number of ARC bytes holding in flight data
399.It Em Header
400number of ARC bytes holding headers
401.It Em Other
402miscellaneous ARC bytes
403.It Em Compressed
404bytes of memory used by ARC caches
405.It Em Uncompressed
406bytes of data stored in ARC caches before compression
407.It Em Ratio
408compression ratio of data cached in the ARC
409.El
410.Ss Swap Stats
411.Bl -tag -width "Uncompressed" -compact
412.It Em Total
413total available swap usage
414.It Em Free
415total free swap usage
416.It Em Inuse
417swap usage
418.It Em \&In
419bytes paged in from swap devices (last interval)
420.It Em Out
421bytes paged out to swap devices (last interval)
422.El
423.Sh ENVIRONMENT
424.Bl -tag -width "Uncompressed"
425.It Ev TOP
426Default set of arguments to
427.Nm .
428.It Ev LC_CTYPE
429The locale to use when displaying the
430.Va argv
431vector when
432.Fl a
433flag is specified.
434.El
435.Sh SEE ALSO
436.Xr kill 1 ,
437.Xr ps 1 ,
438.Xr stty 1 ,
439.Xr getrusage 2 ,
440.Xr humanize_number 3 ,
441.Xr mem 4 ,
442.Xr renice 8
443.Sh AUTHORS
444.An William LeFebvre, EECS Department, Northwestern University
445.Sh BUGS
446The command name for swapped processes should be tracked down, but this
447would make the program run slower.
448.Pp
449As with
450.Xr ps 1 ,
451things can change while
452.Nm
453is collecting information for an update.
454The picture it gives is only a close approximation to reality.
455