1.Dd November 18, 2021 2.Dt TOP 1 3.Os 4.Sh NAME 5.Nm top 6.Nd display and update information about the top cpu processes 7.Sh SYNOPSIS 8.Nm 9.Op Fl abCHIijnPpqSTtuvxz 10.Op Fl d Ar count 11.Op Fl J Ar jail 12.Op Fl m Ar mode 13.Op Fl o Ar field 14.Op Fl p Ar pid 15.Op Fl s Ar time 16.Op Fl U Ar uid 17.Op Ar number 18.Sh DESCRIPTION 19.Nm 20displays the top 21processes on the system and periodically updates this information. 22If standard output is an intelligent terminal (see below) then 23as many processes as will fit on the terminal screen are displayed 24by default. 25Otherwise, a good number of them are shown (around 20). 26Raw cpu percentage is used to rank the processes. 27If 28.Ar number 29is given, then the top 30.Ar number 31processes will be displayed instead of the default. 32.Pp 33.Nm 34makes a distinction between terminals that support advanced capabilities 35and those that do not. 36This distinction affects the choice of defaults for certain options. 37In the remainder of this document, an 38.Dq intelligent 39terminal is one that 40supports cursor addressing, clear screen, and clear to end of line. 41Conversely, a 42.Dq dumb 43terminal is one that does not support such 44features. 45If the output of 46.Nm 47is redirected to a file, it acts as if it were being run on a dumb 48terminal. 49.Pp 50The options are as follows: 51.Bl -tag -width indent 52.It Fl a 53Display command names derived from the argv[] vector, rather than real 54executable name. 55It it useful when you want to watch applications, that 56puts their status information there. 57If the real name differs from argv[0], 58it will be displayed in parenthesis. 59Non-printable characters in the command line are 60encoded in C-style backslash sequences or 61a three digit octal sequences. 62.It Fl b 63Use 64.Dq batch 65mode. 66In this mode, all input from the terminal is 67ignored. 68Interrupt characters (such as ^C and ^\e) still have an effect. 69This is the default on a dumb terminal, or when the output is not a terminal. 70.It Fl C 71Toggle CPU display mode. 72By default top displays the weighted CPU percentage in the WCPU column 73(this is the same value that 74.Xr ps 1 75displays as CPU). 76Each time 77.Fl C 78flag is passed it toggles between 79.Dq raw cpu 80mode and 81.Dq weighted cpu 82mode, showing the 83.Dq CPU 84or the 85.Dq WCPU 86column respectively. 87.It Fl d Ar count 88Show only 89.Ar count 90displays, then exit. 91A display is considered to be one update of the 92screen. 93The default is 1 for dumb terminals. 94Note that for 95.Ar count 96= 1 97no information is available about the percentage of time spent by the CPU in every state. 98.It Fl H 99Display each thread for a multithreaded process individually. 100By default a single summary line is displayed for each process. 101.It Fl I 102Do not display idle processes. 103By default, top displays both active and idle processes. 104.It Fl i 105Use 106.Dq interactive 107mode. 108In this mode, any input is immediately 109read for processing. 110See the section on 111.Dq Interactive Mode 112for an explanation of 113which keys perform what functions. 114After the command is processed, the 115screen will immediately be updated, even if the command was not 116understood. 117This mode is the default when standard output is an 118intelligent terminal. 119.It Fl J Ar jail 120Show only those processes owned by 121.Ar jail . 122This may be either the 123.Ar jid 124or 125.Ar name 126of the jail. 127Use 1280 129to limit to host processes. 130Using this option implies 131.Fl j . 132.It Fl j 133Display the 134.Xr jail 8 135ID. 136.It Fl m Ar mode 137Display statistics in the specified 138.Ar mode . 139Available modes are 140.Cm cpu 141and 142.Cm io . 143Default is 144.Cm cpu . 145.It Fl n 146Use 147.Dq non-interactive 148mode. 149This is identical to 150.Dq batch 151mode. 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.Dq cpu , 157.Dq size , 158.Dq res , 159.Dq time , 160.Dq pri , 161.Dq threads , 162.Dq total , 163.Dq read , 164.Dq write , 165.Dq fault , 166.Dq vcsw , 167.Dq ivcsw , 168.Dq jid , 169.Dq swap , 170or 171.Dq pid . 172.It Fl P 173Display per-cpu CPU usage statistics. 174.It Fl p Ar pid 175Show only the process 176.Ar pid . 177.It Fl q 178Renice 179.Nm 180to -20 so that it will run faster. 181This can be used when the system is 182being very sluggish to improve the possibility of discovering the problem. 183This option can only be used by root. 184.It Fl S 185Show system processes in the display. 186Normally, system processes such as the pager and the swapper are not shown. 187This option makes them visible. 188.It Fl s Ar time 189Set the delay between screen updates to 190.Ar time 191seconds, which may be fractional. 192The default delay between updates is 1 second. 193.It Fl T 194Toggle displaying thread ID (tid) instead of process id (pid). 195.It Fl t 196Do not display the 197.Nm 198process itself. 199.It Fl U Ar username 200Show only those processes owned by 201.Ar username . 202This option currently only accepts usernames and will not understand 203uid numbers. 204.It Fl u 205Do not map uid numbers to usernames. 206Normally, 207.Nm 208will read as much of the file 209.Pa /etc/passwd 210as is necessary to map 211all the user id numbers it encounters into login names. 212This option disables all that, while possibly decreasing execution time. 213The uid numbers are displayed instead of the names. 214.It Fl v 215Write version number information to stderr then exit immediately. 216.It Fl w 217Display approximate swap usage for each process. 218.It Fl z 219Do not display the system idle process. 220.El 221.Pp 222Both 223.Ar count 224and 225.Ar number 226fields can be specified as 227.Dq infinite , 228indicating that they can 229stretch as far as possible. 230This is accomplished by using any proper 231prefix of the keywords 232.Dq infinity , 233.Dq maximum , 234or 235.Dq all . 236Boolean flags are toggles. 237A second specification of any of these options will negate the first. 238.Sh "INTERACTIVE MODE" 239When 240.Nm 241is running in 242.Dq interactive mode , 243it reads commands from the 244terminal and acts upon them accordingly. 245In this mode, the terminal is 246put in 247.Dq CBREAK , 248so that a character will be 249processed as soon as it is typed. 250Almost always, a key will be 251pressed when 252.Nm 253is between displays; that is, while it is waiting for 254.Ar time 255seconds to elapse. 256If this is the case, the command will be 257processed and the display will be updated immediately thereafter 258(reflecting any changes that the command may have specified). 259This 260happens even if the command was incorrect. 261If a key is pressed while 262.Nm 263is in the middle of updating the display, it will finish the update and 264then process the command. 265Some commands require additional information, 266and the user will be prompted accordingly. 267While typing this information 268in, the user's erase and kill keys (as set up by the command 269.Xr stty 1 ) 270are recognized, and a newline terminates the input. 271.Pp 272These commands are currently recognized (^L refers to control-L): 273.Bl -tag -width indent 274.It ^L 275Redraw the screen. 276.It h 277Display a summary of the commands (help screen). 278Version information 279is included in this display. 280.It q 281Quit 282.Nm 283.It d 284Change the number of displays to show (prompt for new number). 285Remember that the next display counts as one, so typing 'd1' will make 286.Nm 287show one final display and then immediately exit. 288.It / 289Display only processes that contain the specified string in their 290command name. 291If displaying arguments is enabled, the arguments are searched 292too. '+' shows all processes. 293.It m 294Toggle the display between 'cpu' and 'io' modes. 295.It n or # 296Change the number of processes to display (prompt for new number). 297.It s 298Change the number of seconds to delay between displays 299(prompt for new number). 300.It S 301Toggle the display of system processes. 302.It a 303Toggle the display of process titles. 304.It k 305Send a signal 306.Pq SIGKILL by default 307to a list of processes. 308This acts similarly to the command 309.Xr kill 1 . 310.It r 311Change the priority 312.Pq the Dq nice 313of a list of processes. 314This acts similarly to 315.Xr renice 8 . 316.It u 317Display only processes owned by a specific set of usernames (prompt for 318username). 319If the username specified is simply 320.Dq + 321or 322.Dq - , 323then processes belonging to all users will be displayed. 324Usernames can be added 325to and removed from the set by prepending them with 326.Dq + 327and 328.Dq - , 329respectively. 330.It o 331Change the order in which the display is sorted. 332The sort key names include 333.Dq cpu , 334.Dq res , 335.Dq size , 336and 337.Dq time. 338The default is cpu. 339.It p 340Display a specific process (prompt for pid). 341If the pid specified is simply 342.Dq + , 343then show all processes. 344.It e 345Display a list of system errors (if any) generated by the last 346command. 347.It H 348Toggle the display of threads. 349.It i or I 350Toggle the display of idle processes. 351.It j 352Toggle the display of 353.Xr jail 8 354ID. 355.It J 356Display only processes owned by a specific jail (prompt for jail). 357If the jail specified is simply 358.Dq + , 359then processes belonging 360to all jails and the host will be displayed. 361This will also enable the display of JID. 362.It P 363Toggle the display of per-CPU statistics. 364.It T 365Toggle display of TID and PID 366.It t 367Toggle the display of the 368.Nm 369process. 370.It w 371Toggle the display of swap usage. 372.It z 373Toggle the display of the system idle process. 374.El 375.Sh "THE DISPLAY" 376The top few lines of the display show general information 377about the state of the system, including 378the last process id assigned to a process (on most systems), 379the three load averages, 380the current time, 381the number of existing processes, 382the number of processes in each state 383(sleeping, running, starting, zombies, and stopped), 384and a percentage of time spent in each of the processor states 385(user, nice, system, and idle). 386It also includes information about physical and virtual memory allocation. 387.Pp 388The remainder of the screen displays information about individual 389processes. 390This display is similar in spirit to 391.Xr ps 1 392but it is not exactly the same. 393PID is the process id, 394JID, when displayed, is the 395.Xr jail 8 396ID corresponding to the process, 397USERNAME is the name of the process's owner (if 398.Fl u 399is specified, a UID column will be substituted for USERNAME), 400PRI is the current priority of the process, 401NICE is the 402.Xr nice 1 403amount, 404SIZE is the total size of the process (text, data, and stack), 405RES is the current amount of resident memory, 406SWAP is the approximate amount of swap, if enabled 407(SIZE, RES and SWAP are given in kilobytes), 408STATE is the current state (one of 409.Dq START , 410.Dq RUN 411(shown as 412.Dq CPUn 413on SMP systems), 414.Dq SLEEP , 415.Dq STOP , 416.Dq ZOMB , 417.Dq WAIT , 418.Dq LOCK , 419or the event on which the process waits), 420C is the processor number on which the process is executing 421(visible only on SMP systems), 422TIME is the number of system and user cpu seconds that the process has used, 423WCPU, when displayed, is the weighted cpu percentage (this is the same 424value that 425.Xr ps 1 426displays as CPU), 427CPU is the raw percentage and is the field that is sorted to determine 428the order of the processes, and 429COMMAND is the name of the command that the process is currently running 430(if the process is swapped out, this column is marked 431.Dq <swapped> ) . 432.Pp 433If a process is in the 434.Dq SLEEP 435or 436.Dq LOCK 437state, 438the state column will report the name of the event or lock on which the 439process is waiting. 440Lock names are prefixed with an asterisk 441.Dq * 442while sleep events 443are not. 444.Sh DESCRIPTION OF MEMORY 445.Bd -literal 446Mem: 61M Active, 86M Inact, 368K Laundry, 22G Wired, 102G Free 447ARC: 15G Total, 9303M MFU, 6155M MRU, 1464K Anon, 98M Header, 35M Other 448 15G Compressed, 27G Uncompressed, 1.75:1 Ratio, 174M Overhead 449Swap: 4096M Total, 532M Free, 13% Inuse, 80K In, 104K Out 450.Ed 451.Ss Physical Memory Stats 452.Bl -tag -width "Uncompressed" -compact 453.It Em Active 454number of bytes active 455.It Em Inact 456number of clean bytes inactive 457.It Em Laundry 458number of dirty bytes queued for laundering 459.It Em Wired 460number of bytes wired down, including IO-level cached file data pages 461.It Em Buf 462number of bytes used for IO-level disk caching 463.It Em Free 464number of bytes free 465.El 466.Ss ZFS ARC Stats 467These stats are only displayed when the ARC is in use. 468.Pp 469.Bl -tag -width "Uncompressed" -compact 470.It Em Total 471number of wired bytes used for the ZFS ARC 472.It Em MRU 473number of ARC bytes holding most recently used data 474.It Em MFU 475number of ARC bytes holding most frequently used data 476.It Em Anon 477number of ARC bytes holding in flight data 478.It Em Header 479number of ARC bytes holding headers 480.It Em Other 481miscellaneous ARC bytes 482.It Em Compressed 483bytes of memory used by ARC caches 484.It Em Uncompressed 485bytes of data stored in ARC caches before compression 486.It Em Ratio 487compression ratio of data cached in the ARC 488.El 489.Ss Swap Stats 490.Bl -tag -width "Uncompressed" -compact 491.It Em Total 492total available swap usage 493.It Em Free 494total free swap usage 495.It Em Inuse 496swap usage 497.It Em \&In 498bytes paged in from swap devices (last interval) 499.It Em Out 500bytes paged out to swap devices (last interval) 501.El 502.Sh ENVIRONMENT 503.Bl -tag -width "Uncompressed" 504.It Ev TOP 505Default set of arguments to 506.Nm . 507.It Ev LC_CTYPE 508The locale to use when displaying the 509.Va argv 510vector when 511.Fl a 512flag is specified. 513.El 514.Sh SEE ALSO 515.Xr kill 1 , 516.Xr ps 1 , 517.Xr stty 1 , 518.Xr getrusage 2 , 519.Xr humanize_number 3 , 520.Xr mem 4 , 521.Xr renice 8 522.Sh AUTHORS 523.An William LeFebvre, EECS Department, Northwestern University 524.Sh BUGS 525The command name for swapped processes should be tracked down, but this 526would make the program run slower. 527.Pp 528As with 529.Xr ps 1 , 530things can change while 531.Nm 532is collecting information for an update. 533The picture it gives is only a close approximation to reality. 534