1.\" $FreeBSD$ 2.Dd November 18, 2021 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 abCHIijnPpqSTtuvxz 11.Op Fl d Ar count 12.Op Fl J Ar jail 13.Op Fl m Ar mode 14.Op Fl o Ar field 15.Op Fl p Ar pid 16.Op Fl s Ar time 17.Op Fl U Ar uid 18.Op Ar number 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 39.Dq intelligent 40terminal is one that 41supports cursor addressing, clear screen, and clear to end of line. 42Conversely, a 43.Dq dumb 44terminal is one that does not support such 45features. 46If the output of 47.Nm 48is redirected to a file, it acts as if it were being run on a dumb 49terminal. 50.Pp 51The options are as follows: 52.Bl -tag -width indent 53.It Fl a 54Display command names derived from the argv[] vector, rather than real 55executable name. 56It it useful when you want to watch applications, that 57puts their status information there. 58If the real name differs from argv[0], 59it will be displayed in parenthesis. 60Non-printable characters in the command line are 61encoded in C-style backslash sequences or 62a three digit octal sequences. 63.It Fl b 64Use 65.Dq batch 66mode. 67In this mode, all input from the terminal is 68ignored. 69Interrupt characters (such as ^C and ^\e) still have an effect. 70This is the default on a dumb terminal, or when the output is not a terminal. 71.It Fl C 72Toggle CPU display mode. 73By default top displays the weighted CPU percentage in the WCPU column 74(this is the same value that 75.Xr ps 1 76displays as CPU). 77Each time 78.Fl C 79flag is passed it toggles between 80.Dq raw cpu 81mode and 82.Dq weighted cpu 83mode, showing the 84.Dq CPU 85or the 86.Dq WCPU 87column respectively. 88.It Fl d Ar count 89Show only 90.Ar count 91displays, then exit. 92A display is considered to be one update of the 93screen. 94The default is 1 for dumb terminals. 95Note that for 96.Ar count 97= 1 98no information is available about the percentage of time spent by the CPU in every state. 99.It Fl H 100Display each thread for a multithreaded process individually. 101By default a single summary line is displayed for each process. 102.It Fl I 103Do not display idle processes. 104By default, top displays both active and idle processes. 105.It Fl i 106Use 107.Dq interactive 108mode. 109In this mode, any input is immediately 110read for processing. 111See the section on 112.Dq Interactive Mode 113for an explanation of 114which keys perform what functions. 115After the command is processed, the 116screen will immediately be updated, even if the command was not 117understood. 118This mode is the default when standard output is an 119intelligent terminal. 120.It Fl J Ar jail 121Show only those processes owned by 122.Ar jail . 123This may be either the 124.Ar jid 125or 126.Ar name 127of the jail. 128Use 1290 130to limit to host processes. 131Using this option implies 132.Fl j . 133.It Fl j 134Display the 135.Xr jail 8 136ID. 137.It Fl m Ar mode 138Display statistics in the specified 139.Ar mode . 140Available modes are 141.Cm cpu 142and 143.Cm io . 144Default is 145.Cm cpu . 146.It Fl n 147Use 148.Dq non-interactive 149mode. 150This is identical to 151.Dq batch 152mode. 153.It Fl o Ar field 154Sort the process display area on the specified field. 155The field name 156is the name of the column as seen in the output, but in lower case: 157.Dq cpu , 158.Dq size , 159.Dq res , 160.Dq time , 161.Dq pri , 162.Dq threads , 163.Dq total , 164.Dq read , 165.Dq write , 166.Dq fault , 167.Dq vcsw , 168.Dq ivcsw , 169.Dq jid , 170.Dq swap , 171or 172.Dq pid . 173.It Fl P 174Display per-cpu CPU usage statistics. 175.It Fl p Ar pid 176Show only the process 177.Ar pid . 178.It Fl q 179Renice 180.Nm 181to -20 so that it will run faster. 182This can be used when the system is 183being very sluggish to improve the possibility of discovering the problem. 184This option can only be used by root. 185.It Fl S 186Show system processes in the display. 187Normally, system processes such as the pager and the swapper are not shown. 188This option makes them visible. 189.It Fl s Ar time 190Set the delay between screen updates to 191.Ar time 192seconds, which may be fractional. 193The default delay between updates is 1 second. 194.It Fl T 195Toggle displaying thread ID (tid) instead of process id (pid). 196.It Fl t 197Do not display the 198.Nm 199process itself. 200.It Fl U Ar username 201Show only those processes owned by 202.Ar username . 203This option currently only accepts usernames and will not understand 204uid numbers. 205.It Fl u 206Do not map uid numbers to usernames. 207Normally, 208.Nm 209will read as much of the file 210.Pa /etc/passwd 211as is necessary to map 212all the user id numbers it encounters into login names. 213This option disables all that, while possibly decreasing execution time. 214The uid numbers are displayed instead of the names. 215.It Fl v 216Write version number information to stderr then exit immediately. 217.It Fl w 218Display approximate swap usage for each process. 219.It Fl z 220Do not display the system idle process. 221.El 222.Pp 223Both 224.Ar count 225and 226.Ar number 227fields can be specified as 228.Dq infinite , 229indicating that they can 230stretch as far as possible. 231This is accomplished by using any proper 232prefix of the keywords 233.Dq infinity , 234.Dq maximum , 235or 236.Dq all . 237Boolean flags are toggles. 238A second specification of any of these options will negate the first. 239.Sh "INTERACTIVE MODE" 240When 241.Nm 242is running in 243.Dq interactive mode , 244it reads commands from the 245terminal and acts upon them accordingly. 246In this mode, the terminal is 247put in 248.Dq CBREAK , 249so that a character will be 250processed as soon as it is typed. 251Almost always, a key will be 252pressed when 253.Nm 254is between displays; that is, while it is waiting for 255.Ar time 256seconds to elapse. 257If this is the case, the command will be 258processed and the display will be updated immediately thereafter 259(reflecting any changes that the command may have specified). 260This 261happens even if the command was incorrect. 262If a key is pressed while 263.Nm 264is in the middle of updating the display, it will finish the update and 265then process the command. 266Some commands require additional information, 267and the user will be prompted accordingly. 268While typing this information 269in, the user's erase and kill keys (as set up by the command 270.Xr stty 1 ) 271are recognized, and a newline terminates the input. 272.Pp 273These commands are currently recognized (^L refers to control-L): 274.Bl -tag -width indent 275.It ^L 276Redraw the screen. 277.It h 278Display a summary of the commands (help screen). 279Version information 280is included in this display. 281.It q 282Quit 283.Nm 284.It d 285Change the number of displays to show (prompt for new number). 286Remember that the next display counts as one, so typing 'd1' will make 287.Nm 288show one final display and then immediately exit. 289.It / 290Display only processes that contain the specified string in their 291command name. 292If displaying arguments is enabled, the arguments are searched 293too. '+' shows all processes. 294.It m 295Toggle the display between 'cpu' and 'io' modes. 296.It n or # 297Change the number of processes to display (prompt for new number). 298.It s 299Change the number of seconds to delay between displays 300(prompt for new number). 301.It S 302Toggle the display of system processes. 303.It a 304Toggle the display of process titles. 305.It k 306Send a signal 307.Pq SIGKILL by default 308to a list of processes. 309This acts similarly to the command 310.Xr kill 1 . 311.It r 312Change the priority 313.Pq the Dq nice 314of a list of processes. 315This acts similarly to 316.Xr renice 8 . 317.It u 318Display only processes owned by a specific set of usernames (prompt for 319username). 320If the username specified is simply 321.Dq + 322or 323.Dq - , 324then processes belonging to all users will be displayed. 325Usernames can be added 326to and removed from the set by prepending them with 327.Dq + 328and 329.Dq - , 330respectively. 331.It o 332Change the order in which the display is sorted. 333The sort key names include 334.Dq cpu , 335.Dq res , 336.Dq size , 337and 338.Dq time. 339The default is cpu. 340.It p 341Display a specific process (prompt for pid). 342If the pid specified is simply 343.Dq + , 344then show all processes. 345.It e 346Display a list of system errors (if any) generated by the last 347command. 348.It H 349Toggle the display of threads. 350.It i or I 351Toggle the display of idle processes. 352.It j 353Toggle the display of 354.Xr jail 8 355ID. 356.It J 357Display only processes owned by a specific jail (prompt for jail). 358If the jail specified is simply 359.Dq + , 360then processes belonging 361to all jails and the host will be displayed. 362This will also enable the display of JID. 363.It P 364Toggle the display of per-CPU statistics. 365.It T 366Toggle display of TID and PID 367.It t 368Toggle the display of the 369.Nm 370process. 371.It w 372Toggle the display of swap usage. 373.It z 374Toggle the display of the system idle process. 375.El 376.Sh "THE DISPLAY" 377The top few lines of the display show general information 378about the state of the system, including 379the last process id assigned to a process (on most systems), 380the three load averages, 381the current time, 382the number of existing processes, 383the number of processes in each state 384(sleeping, running, starting, zombies, and stopped), 385and a percentage of time spent in each of the processor states 386(user, nice, system, and idle). 387It also includes information about physical and virtual memory allocation. 388.Pp 389The remainder of the screen displays information about individual 390processes. 391This display is similar in spirit to 392.Xr ps 1 393but it is not exactly the same. 394PID is the process id, 395JID, when displayed, is the 396.Xr jail 8 397ID corresponding to the process, 398USERNAME is the name of the process's owner (if 399.Fl u 400is specified, a UID column will be substituted for USERNAME), 401PRI is the current priority of the process, 402NICE is the 403.Xr nice 1 404amount, 405SIZE is the total size of the process (text, data, and stack), 406RES is the current amount of resident memory, 407SWAP is the approximate amount of swap, if enabled 408(SIZE, RES and SWAP are given in kilobytes), 409STATE is the current state (one of 410.Dq START , 411.Dq RUN 412(shown as 413.Dq CPUn 414on SMP systems), 415.Dq SLEEP , 416.Dq STOP , 417.Dq ZOMB , 418.Dq WAIT , 419.Dq LOCK , 420or the event on which the process waits), 421C is the processor number on which the process is executing 422(visible only on SMP systems), 423TIME is the number of system and user cpu seconds that the process has used, 424WCPU, when displayed, is the weighted cpu percentage (this is the same 425value that 426.Xr ps 1 427displays as CPU), 428CPU is the raw percentage and is the field that is sorted to determine 429the order of the processes, and 430COMMAND is the name of the command that the process is currently running 431(if the process is swapped out, this column is marked 432.Dq <swapped> ) . 433.Pp 434If a process is in the 435.Dq SLEEP 436or 437.Dq LOCK 438state, 439the state column will report the name of the event or lock on which the 440process is waiting. 441Lock names are prefixed with an asterisk 442.Dq * 443while sleep events 444are not. 445.Sh DESCRIPTION OF MEMORY 446.Bd -literal 447Mem: 61M Active, 86M Inact, 368K Laundry, 22G Wired, 102G Free 448ARC: 15G Total, 9303M MFU, 6155M MRU, 1464K Anon, 98M Header, 35M Other 449 15G Compressed, 27G Uncompressed, 1.75:1 Ratio, 174M Overhead 450Swap: 4096M Total, 532M Free, 13% Inuse, 80K In, 104K Out 451.Ed 452.Ss Physical Memory Stats 453.Bl -tag -width "Uncompressed" -compact 454.It Em Active 455number of bytes active 456.It Em Inact 457number of clean bytes inactive 458.It Em Laundry 459number of dirty bytes queued for laundering 460.It Em Wired 461number of bytes wired down, including IO-level cached file data pages 462.It Em Buf 463number of bytes used for IO-level disk caching 464.It Em Free 465number of bytes free 466.El 467.Ss ZFS ARC Stats 468These stats are only displayed when the ARC is in use. 469.Pp 470.Bl -tag -width "Uncompressed" -compact 471.It Em Total 472number of wired bytes used for the ZFS ARC 473.It Em MRU 474number of ARC bytes holding most recently used data 475.It Em MFU 476number of ARC bytes holding most frequently used data 477.It Em Anon 478number of ARC bytes holding in flight data 479.It Em Header 480number of ARC bytes holding headers 481.It Em Other 482miscellaneous ARC bytes 483.It Em Compressed 484bytes of memory used by ARC caches 485.It Em Uncompressed 486bytes of data stored in ARC caches before compression 487.It Em Ratio 488compression ratio of data cached in the ARC 489.El 490.Ss Swap Stats 491.Bl -tag -width "Uncompressed" -compact 492.It Em Total 493total available swap usage 494.It Em Free 495total free swap usage 496.It Em Inuse 497swap usage 498.It Em \&In 499bytes paged in from swap devices (last interval) 500.It Em Out 501bytes paged out to swap devices (last interval) 502.El 503.Sh ENVIRONMENT 504.Bl -tag -width "Uncompressed" 505.It Ev TOP 506Default set of arguments to 507.Nm . 508.It Ev LC_CTYPE 509The locale to use when displaying the 510.Va argv 511vector when 512.Fl a 513flag is specified. 514.El 515.Sh SEE ALSO 516.Xr kill 1 , 517.Xr ps 1 , 518.Xr stty 1 , 519.Xr getrusage 2 , 520.Xr humanize_number 3 , 521.Xr mem 4 , 522.Xr renice 8 523.Sh AUTHORS 524.An William LeFebvre, EECS Department, Northwestern University 525.Sh BUGS 526The command name for swapped processes should be tracked down, but this 527would make the program run slower. 528.Pp 529As with 530.Xr ps 1 , 531things can change while 532.Nm 533is collecting information for an update. 534The picture it gives is only a close approximation to reality. 535