.\" $OpenBSD: top.1,v 1.53 2009/12/22 18:14:23 jmc Exp $ .\" .\" Copyright (c) 1997, Jason Downs. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS .\" OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED .\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE .\" DISCLAIMED. IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, .\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES .\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR .\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER .\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .Dd $Mdocdate: December 22 2009 $ .Dt TOP 1 .Os .Sh NAME .Nm top .Nd display and update information about the top CPU processes .Sh SYNOPSIS .Nm top .Bk -words .Op Fl 1bCIinqSTu .Op Fl d Ar count .Op Fl g Ar string .Op Fl o Ar field .Op Fl p Ar pid .Op Fl s Ar time .Op Fl U Ar user .Op Ar number .Ek .Sh DESCRIPTION .Nm displays the top processes on the system and periodically updates this information. If standard output is an intelligent terminal (see below) then as many processes as will fit on the terminal screen are displayed by default. Otherwise, a good number of them are shown (around 20). Raw CPU percentage is used to rank the processes. If .Ar number is given, then the top .Ar number processes will be displayed instead of the default. .Pp .Nm makes a distinction between terminals that support advanced capabilities and those that do not. This distinction affects the choice of defaults for certain options. In the remainder of this document, an .Em intelligent terminal is one that supports cursor addressing, clear screen, and clear to end of line. Conversely, a .Em dumb terminal is one that does not support such features. If the output of .Nm is redirected to a file, it acts as if it were being run on a dumb terminal. .Pp The options are as follows: .Bl -tag -width Ds .It Fl 1 Display CPU statistics on a single line instead of a line per CPU. .It Fl b Use .Em batch mode. In this mode, all input from the terminal is ignored. Interrupt characters (such as .Ql ^C and .Ql ^\e ) still have an effect. This is the default on a dumb terminal, or when the output is not a terminal. .It Fl C Show command line arguments as well as the process itself. .It Fl d Ar count Show only .Ar count displays, then exit. A display is considered to be one update of the screen. This option allows the user to select the number of displays to be shown before .Nm automatically exits. For intelligent terminals, no upper limit is set. The default is 1 for dumb terminals. .It Fl g Ar string Display only processes that contain .Ar string in their command name. .It Fl I Do not display idle processes. By default, .Nm displays both active and idle processes. .It Fl i Use .Em interactive mode. In this mode, any input is immediately read for processing. See the section on .Sx INTERACTIVE MODE for an explanation of which keys perform what functions. After the command is processed, the screen will immediately be updated, even if the command was not understood. This mode is the default when standard output is an intelligent terminal. .It Fl n Use .Em non-interactive mode. This is identical to .Em batch mode. .It Fl o Ar field Sort the process display area using the specified .Ar field as the primary key. The field name is the name of the column as seen in the output, but in lower case. The .Ox version of .Nm supports .Ar cpu , .Ar size , .Ar res , .Ar time , and .Ar pri . .It Fl p Ar pid Show only the process .Ar pid . .It Fl q Renice .Nm to \-20 so that it will run faster. This can be used when the system is being very sluggish to improve the possibility of discovering the problem. This option can only be used by root. .It Fl S Show system processes in the display. Normally, system processes such as the pager and the swapper are not shown. This option makes them visible. .It Fl s Ar time Set the delay between screen updates to .Ar time seconds. The value may be fractional, to permit delays of less than 1 second. The default delay between updates is 5 seconds. .It Fl T Show process threads in the display. Normally, only the main process is shown. This option makes all threads visible. .It Fl U Ar user Show only those processes owned by .Ar user . This option currently only accepts usernames and will not understand UID numbers. .It Fl u Do not take the time to map UID numbers to usernames. Normally, .Nm will read as much of the password database as is necessary to map all the user ID numbers it encounters into login names. This option disables all that, while possibly decreasing execution time. The UID numbers are displayed instead of the names. .El .Pp Both .Ar count and .Ar number fields can be specified as .Li infinite , indicating that they can stretch as far as possible. This is accomplished by using any proper prefix of the keywords .Li infinity , .Li maximum , or .Li all . The default for .Ar count on an intelligent terminal is, in fact, .Li infinity . .Pp The environment variable .Ev TOP is examined for options before the command line is scanned. This enables a user to set his or her own defaults. The number of processes to display can also be specified in the environment variable .Ev TOP . .Pp The options .Fl I , .Fl S , and .Fl u are actually toggles. A second specification of any of these options will negate the first. Thus a user who has the environment variable .Ev TOP set to .Dq -I may use the command .Dq top -I to see idle processes. .Sh INTERACTIVE MODE When .Nm is running in .Em interactive mode , it reads commands from the terminal and acts upon them accordingly. In this mode, the terminal is put in .Dv CBREAK , so that a character will be processed as soon as it is typed. Almost always, a key will be pressed when .Nm is between displays; that is, while it is waiting for .Ar time seconds to elapse. If this is the case, the command will be processed and the display will be updated immediately thereafter (reflecting any changes that the command may have specified). This happens even if the command was incorrect. If a key is pressed while .Nm is in the middle of updating the display, it will finish the update and then process the command. Some commands require additional information, and the user will be prompted accordingly. While typing this information in, the user's erase and kill keys (as set up by the command .Xr stty 1 ) are recognized, and a newline terminates the input. .Pp These commands are currently recognized (^L refers to control-L): .Bl -tag -width XxXXXX .It h \*(Ba \&? Display a summary of the commands (help screen). .It ^L Redraw the screen. .It q Quit .Nm . .El .Bl -tag -width XxXXXX .It + Reset any filters put in place by the .Sq g , .Sq p , and .Sq u interactive commands, or their command line equivalents, or any process highlighting put in place by the .Sq P interactive command. .It 1 Display CPU statistics on a single line instead of a line per CPU. .It C Toggle the display of process command line arguments. .It d Ar count Show only .Ar count displays, then exit. .It e Display a list of system errors (if any) generated by the last .Li kill or .Li renice command. .It g Ar string Display only processes that contain .Ar string in their command name. .Sq g+ shows all processes. .It I \*(Ba i Toggle the display of idle processes. .It Xo k .Op - Ns Ar sig .Ar pid .Xc Send signal .No - Ns Ar sig .Pf ( Dv TERM by default) to process .Ar pid . This acts similarly to the command .Xr kill 1 . .It n\*(Ba# Ar count Show .Ar count processes. .It o Ar field Sort the process display area using the specified .Ar field as the primary key. Values are the same as for the .Fl o flag, as detailed above. .It P Ar pid Highlight a specific process, selected by .Ar pid . .Sq P+ removes process highlighting. .It p Ar pid Show only the process .Ar pid . .Sq p+ shows all processes. .It r Ar count pid Change the priority (the .Em nice ) of a list of processes to .Ar count for process .Ar pid . This acts similarly to the command .Xr renice 8 . .It S Toggle the display of system processes. .It s Ar time Set the delay between screen updates to .Ar time seconds. .It T Toggle the display of process threads. .It u Ar user Show only those processes owned by .Ar user . .Sq u+ shows processes belonging to all users. .El .Sh THE DISPLAY .\" The actual display varies depending on the specific variant of Unix .\" that the machine is running. This description may not exactly match .\" what is seen by top running on this particular machine. Differences .\" are listed at the end of this manual entry. .\" .Pp The top few lines of the display show general information about the state of the system, including .\" the last process ID assigned to a process, .\" (on most systems), the three load average numbers, the current time, the number of existing processes, the number of processes in each state (starting, running, idle, stopped, zombie, dead, and on processor), and a percentage of time spent in each of the processor states (user, nice, system, interrupt, and idle). It also includes information about physical and virtual memory allocation. The load average numbers give the number of jobs in the run queue averaged over 1, 5, and 15 minutes. .Pp The remainder of the screen displays information about individual processes. This display is similar in spirit to .Xr ps 1 but it is not exactly the same. The following fields are displayed: .Bl -tag -width USERNAME -offset indent .It PID The process ID. .It USERNAME The name of the process's owner. .It UID Used instead of USERNAME if .Fl u is specified. .It PRI The current priority of the process. .It NICE The nice amount (in the range \-20 to 20). .It SIZE The total size of the process (the text, data, and stack segments). .It RES The current amount of resident memory. .It STATE The current state (one of .Li start , .Li run , .Li sleep , .Li stop , .Li idle , .Li zomb , .Li dead , or .Li onproc ) . On multi-processor systems, this is followed by a slash and the CPU number on which the process is bound. .It WAIT A description of the wait channel the process is sleeping on if it's asleep. .It TIME The number of system and user CPU seconds that the process has used. .It CPU The raw percentage of CPU usage and the default field on which the display is sorted. .It COMMAND The name of the command that the process is currently running. (If the process is swapped out, this column is enclosed by angle brackets.) .El .Sh ENVIRONMENT .Bl -tag -width Ev .It Ev TOP User-configurable defaults for options. .El .Sh FILES .Bl -tag -width "/etc/passwdXXX" -compact .It Pa /dev/kmem kernel memory .It Pa /dev/mem physical memory .It Pa /etc/passwd used to map user ID to user .It Pa /bsd kernel image .El .Sh SEE ALSO .Xr fstat 1 , .Xr kill 1 , .Xr netstat 1 , .Xr ps 1 , .Xr stty 1 , .Xr systat 1 , .Xr mem 4 , .Xr iostat 8 , .Xr pstat 8 , .Xr renice 8 , .Xr vmstat 8 .Sh AUTHORS William LeFebvre, EECS Department, Northwestern University .Sh BUGS As with .Xr ps 1 , things can change while .Nm is collecting information for an update. The picture it gives is only a close approximation to reality.