xref: /freebsd/usr.bin/top/top.1 (revision b1de37fadd8d5d672065b6a9f9839b021fbeb433)
1.\" $FreeBSD$
2.Dd September 20, 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.
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.Pp
196The display of command names changes according to the locale.
197If command names displayed in the locale settings are recognized as
198non-display characters, they are displayed in three digit octal sequence.
199.Sh "INTERACTIVE MODE"
200When
201.Nm
202is running in \*(lqinteractive mode\*(rq, it reads commands from the
203terminal and acts upon them accordingly.
204In this mode, the terminal is
205put in \*(lqCBREAK\*(rq, so that a character will be
206processed as soon as it is typed.
207Almost always, a key will be
208pressed when
209.Nm
210is between displays; that is, while it is waiting for
211.Ar time
212seconds to elapse.
213If this is the case, the command will be
214processed and the display will be updated immediately thereafter
215(reflecting any changes that the command may have specified).
216This
217happens even if the command was incorrect.
218If a key is pressed while
219.Nm
220is in the middle of updating the display, it will finish the update and
221then process the command.
222Some commands require additional information,
223and the user will be prompted accordingly.
224While typing this information
225in, the user's erase and kill keys (as set up by the command
226.Xr stty 1 )
227are recognized, and a newline terminates the input.
228.Pp
229These commands are currently recognized (^L refers to control-L):
230.Bl -tag -width indent
231.It ^L
232Redraw the screen.
233.It h
234Display a summary of the commands (help screen).
235Version information
236is included in this display.
237.It q
238Quit
239.Nm
240.It d
241Change the number of displays to show (prompt for new number).
242Remember that the next display counts as one, so typing
243.It d1
244will make
245.Nm
246show one final display and then immediately exit.
247.It m
248Toggle the display between 'cpu' and 'io' modes.
249.It n or #
250Change the number of processes to display (prompt for new number).
251.It s
252Change the number of seconds to delay between displays
253(prompt for new number).
254.It S
255Toggle the display of system processes.
256.It a
257Toggle the display of process titles.
258.It k
259Send a signal (\*(lqkill\*(rq by default) to a list of processes.
260This acts similarly to the command
261.Xr kill 1 .
262.It r
263Change the priority (the \*(lqnice\*(rq) of a list of processes.
264This acts similarly to
265.Xr renice 8 .
266.It u
267Display only processes owned by a specific set of usernames (prompt for
268username).
269If the username specified is simply \*(lq+\*(rq or \*(lq-\*(rq,
270then processes belonging to all users will be displayed.
271Usernames can be added
272to and removed from the set by prepending them with \*(lq+\*(rq and
273\*(lq-\*(rq, respectively.
274.It o
275Change the order in which the display is sorted.
276The sort key names include
277\*(lqcpu\*(rq, \*(lqres\*(rq, \*(lqsize\*(rq,
278\*(lqtime\*(rq.
279The default is cpu.
280.It p
281Display a specific process (prompt for pid).
282If the pid specified is simply \*(lq+\*(rq, then show all processes.
283.It e
284Display a list of system errors (if any) generated by the last
285command.
286.It B H
287Toggle the display of threads.
288.It i or I
289Toggle the display of idle processes.
290.It j
291Toggle the display of
292.Xr jail 8
293ID.
294.It J
295Display only processes owned by a specific jail (prompt for jail).
296If the jail specified is simply \*(lq+\*(rq, then processes belonging
297to all jails and the host will be displayed.
298This will also enable the display of JID.
299.It P
300Toggle the display of per-CPU statistics.
301.It T
302Toggle display of TID and PID
303.It t
304Toggle the display of the
305.Nm
306process.
307.It w
308Toggle the display of swap usage.
309.It z
310Toggle the display of the system idle process.
311.El
312.Sh "THE DISPLAY"
313The top few lines of the display show general information
314about the state of the system, including
315the last process id assigned to a process (on most systems),
316the three load averages,
317the current time,
318the number of existing processes,
319the number of processes in each state
320(sleeping, running, starting, zombies, and stopped),
321and a percentage of time spent in each of the processor states
322(user, nice, system, and idle).
323It also includes information about physical and virtual memory allocation.
324.Pp
325The remainder of the screen displays information about individual
326processes.
327This display is similar in spirit to
328.Xr ps 1
329but it is not exactly the same.
330PID is the process id,
331JID, when displayed, is the
332.Xr jail 8
333ID corresponding to the process,
334USERNAME is the name of the process's owner (if
335.Fl u
336is specified, a UID column will be substituted for USERNAME),
337PRI is the current priority of the process,
338NICE is the
339.Xr nice 1
340amount,
341SIZE is the total size of the process (text, data, and stack),
342RES is the current amount of resident memory,
343SWAP is the approximate amount of swap, if enabled
344(SIZE, RES and SWAP are given in kilobytes),
345STATE is the current state (one of \*(lqSTART\*(rq, \*(lqRUN\*(rq
346(shown as \*(lqCPUn\*(rq on SMP systems), \*(lqSLEEP\*(rq, \*(lqSTOP\*(rq,
347\*(lqZOMB\*(rq, \*(lqWAIT\*(rq, \*(lqLOCK\*(rq or the event on which the
348process waits),
349C is the processor number on which the process is executing
350(visible only on SMP systems),
351TIME is the number of system and user cpu seconds that the process has used,
352WCPU, when displayed, is the weighted cpu percentage (this is the same
353value that
354.Xr ps 1
355displays as CPU),
356CPU is the raw percentage and is the field that is sorted to determine
357the order of the processes, and
358COMMAND is the name of the command that the process is currently running
359(if the process is swapped out, this column is marked \*(lq<swapped>\*(rq).
360.Pp
361If a process is in the \*(lqSLEEP\*(rq or \*(lqLOCK\*(rq state,
362the state column will report the name of the event or lock on which the
363process is waiting.
364Lock names are prefixed with an asterisk \*(lq*\*(rq while sleep events
365are not.
366.Sh DESCRIPTION OF MEMORY
367.Bd -literal
368Mem: 61M Active, 86M Inact, 368K Laundry, 22G Wired, 102G Free
369ARC: 15G Total, 9303M MFU, 6155M MRU, 1464K Anon, 98M Header, 35M Other
370     15G Compressed, 27G Uncompressed, 1.75:1 Ratio, 174M Overhead
371Swap: 4096M Total, 532M Free, 13% Inuse, 80K In, 104K Out
372.Ed
373.Ss Physical Memory Stats
374.Bl -tag -width "Uncompressed" -compact
375.It Em Active
376number of bytes active
377.It Em Inact
378number of clean bytes inactive
379.It Em Laundry
380number of dirty bytes queued for laundering
381.It Em Wired
382number of bytes wired down, including IO-level cached file data pages
383.It Em Buf
384number of bytes used for IO-level disk caching
385.It Em Free
386number of bytes free
387.El
388.Ss ZFS ARC Stats
389These stats are only displayed when the ARC is in use.
390.Pp
391.Bl -tag -width "Uncompressed" -compact
392.It Em Total
393number of wired bytes used for the ZFS ARC
394.It Em MRU
395number of ARC bytes holding most recently used data
396.It Em MFU
397number of ARC bytes holding most frequently used data
398.It Em Anon
399number of ARC bytes holding in flight data
400.It Em Header
401number of ARC bytes holding headers
402.It Em Other
403miscellaneous ARC bytes
404.It Em Compressed
405bytes of memory used by ARC caches
406.It Em Uncompressed
407bytes of data stored in ARC caches before compression
408.It Em Ratio
409compression ratio of data cached in the ARC
410.El
411.Ss Swap Stats
412.Bl -tag -width "Uncompressed" -compact
413.It Em Total
414total available swap usage
415.It Em Free
416total free swap usage
417.It Em Inuse
418swap usage
419.It Em \&In
420bytes paged in from swap devices (last interval)
421.It Em Out
422bytes paged out to swap devices (last interval)
423.El
424.Sh ENVIRONMENT
425.Bl -tag -width "Uncompressed"
426.It Ev TOP
427Default set of arguments to
428.Nm .
429.El
430.Sh SEE ALSO
431.Xr kill 1 ,
432.Xr ps 1 ,
433.Xr stty 1 ,
434.Xr getrusage 2 ,
435.Xr humanize_number 3 ,
436.Xr mem 4 ,
437.Xr renice 8
438.Sh AUTHORS
439.An William LeFebvre, EECS Department, Northwestern University
440.Sh BUGS
441The command name for swapped processes should be tracked down, but this
442would make the program run slower.
443.Pp
444As with
445.Xr ps 1 ,
446things can change while
447.Nm
448is collecting information for an update.
449The picture it gives is only a close approximation to reality.
450