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TOP(1)				       Linux User's Manual				   TOP(1)

NAME
       top - display Linux tasks

SYNOPSIS
       top -hv | -bcHisS -d delay -n iterations -p pid [, pid ...]

       The traditional switches '-' and whitespace are optional.

DESCRIPTION
       The  top  program  provides  a dynamic real-time view of a running system.  It can display
       system summary information as well as a list of tasks currently being managed by the Linux
       kernel.	 The  types  of system summary information shown and the types, order and size of
       information displayed for tasks are all user configurable and that  configuration  can  be
       made persistent across restarts.

       The program provides a limited interactive interface for process manipulation as well as a
       much more extensive interface for personal configuration  --  encompassing every aspect of
       its  operation.	 And  while  top is referred to throughout this document, you are free to
       name the program anything you wish.  That new  name,  possibly  an  alias,  will  then  be
       reflected on top's display and used when reading and writing a configuration file.

OVERVIEW
   Documentation
       The remaining Table of Contents
	   1. COMMAND-LINE Options
	   2. FIELDS / Columns
	      a. DESCRIPTIONS of Fields
	      b. SELECTING and ORDERING Columns
	   3. INTERACTIVE Commands
	      a. GLOBAL Commands
	      b. SUMMARY Area Commands
	      c. TASK Area Commands
	      d. COLOR Mapping
	   4. ALTERNATE-DISPLAY Mode
	      a. WINDOWS Overview
	      b. COMMANDS for Windows
	   5. FILES
	      a. SYSTEM Configuration File
	      b. PERSONAL Configuration File
	   6. STUPID TRICKS Sampler
	      a. Kernel Magic
	      b. Bouncing Windows
	      c. The Big Bird Window
	   7. BUGS, 8. HISTORY Former top, 9. AUTHOR, 10. SEE ALSO

   Operation
       When  operating top, the two most important keys are help ('h' or '?') and quit ('q') key.
       Alternatively, you could simply use the traditional interrupt key ('^C') when you're done.

       When you start top for the first time, you'll be presented  with  the  traditional  screen
       elements: 1) Summary Area; 2) Message/Prompt Line; 3) Columns Header; 4) Task Area.  There
       will, however, be some differences when compared to the former top.

       Highlighting
	  Summary_Area: There is no highlighting for load/uptime and only values are  highlighted
	  for other elements.

	  Task_Area:  Tasks  running  (or ready to run) will be highlighted, and bold is only one
	  way of emphasizing such processes.

       Content/Labels
	  Summary_Area: The program name is shown, perhaps a symlink or alias.	The Cpu(s)  state
	  label hints at other possibilities.  The memory stats use a lower case 'k'.

	  Columns_Header: Will show a new field and some changed labels.  More new fields will be
	  found as you customize your top.

       Note: the width of top's display will be limited to 512 positions.  Displaying all  fields
       requires a minimum of 160 characters.  The remaining width could be used for the 'Command'
       column.

   Startup Defaults
       The following startup defaults assume no configuration file, thus no user  customizations.
       Even so, items shown with an asterisk ('*') could be overridden through the command-line.

	   Global_defaults
	      'A' - Alt display      Off (full-screen)
	    * 'd' - Delay time	     3.0 seconds
	      'I' - Irix mode	     On  (no, 'solaris' smp)
	    * 'p' - PID monitoring   Off
	    * 's' - Secure mode      Off (unsecured)
	      'B' - Bold enable      Off
	   Summary_Area_defaults
	      'l' - Load Avg/Uptime  On  (thus program name)
	      't' - Task/Cpu states  On  (1+1 lines, see '1')
	      'm' - Mem/Swap usage   On  (2 lines worth)
	      '1' - Single Cpu	     On  (thus 1 line if smp)
	   Task_Area_defaults
	      'b' - Bold hilite      On  (not 'reverse')
	    * 'c' - Command line     Off (name, not cmdline)
	    * 'H' - Threads	     Off (show all threads)
	    * 'i' - Idle tasks	     On  (show all tasks)
	      'R' - Reverse sort     On  (pids high-to-low)
	    * 'S' - Cumulative time  Off (no, dead children)
	      'x' - Column hilite    Off (no, sort field)
	      'y' - Row hilite	     On  (yes, running tasks)
	      'z' - color/mono	     Off (no, colors)

1. COMMAND-LINE Options
       The command-line syntax for top consists of:

	    -hv | -bcHisS -d delay -n iterations -p pid [,pid...]

       The typically mandatory switches ('-') and even whitespace are completely optional.

       -b : Batch mode operation
	    Starts  top  in  'Batch  mode',  which could be useful for sending output from top to
	    other programs or to a file.  In this mode, top will not accept input and runs  until
	    the iterations limit you've set with the '-n' command-line option or until killed.

       -c : Command line/Program name toggle
	    Starts  top with the last remembered 'c' state reversed.  Thus, if top was displaying
	    command lines, now that field will show program names, and visa versa.  See  the  'c'
	    interactive command for additional information.

       -d : Delay time interval as:  -d ss.tt (seconds.tenths)
	    Specifies  the delay between screen updates, and overrides the corresponding value in
	    one's personal configuration file or the startup default.  Later this can be  changed
	    with the 'd' or 's' interactive commands.

	    Fractional	seconds are honored, but a negative number is not allowed.  In all cases,
	    however, such changes are prohibited if top is running in 'Secure mode',  except  for
	    root  (unless  the	's' command-line option was used).  For additional information on
	    'Secure mode' see topic 5a. SYSTEM Configuration File.

       -h : Help
	    Show library version and the usage prompt, then quit.

       -H : Threads toggle
	    Starts top with the last remembered 'H' state reversed.  When this toggle is On,  all
	    individual	threads  will  be  displayed.  Otherwise, top displays a summation of all
	    threads in a process.

       -i : Idle Processes toggle
	    Starts top with the last remembered 'i' state reversed.  When  this  toggle  is  Off,
	    tasks that are idled or zombied will not be displayed.

       -n : Number of iterations limit as:  -n number
	    Specifies the maximum number of iterations, or frames, top should produce before end-
	    ing.

       -u : Monitor by user as:  -u somebody
	    Monitor only processes with an effective UID or user name matching that given.

       -U : Monitor by user as:  -U somebody
	    Monitor only processes with a UID or user name matching  that  given.   This  matches
	    real, effective, saved, and filesystem UIDs.

       -p : Monitor PIDs as:  -pN1 -pN2 ...  or  -pN1, N2 [,...]
	    Monitor only processes with specified process IDs.	This option can be given up to 20
	    times, or you can provide a comma delimited list with up  to  20  pids.   Co-mingling
	    both approaches is permitted.

	    This  is  a command-line option only.  And should you wish to return to normal opera-
	    tion, it is not necessary to quit and and restart top  --  just issue the '='  inter-
	    active command.

       -s : Secure mode operation
	    Starts  top  with  secure  mode  forced, even for root.  This mode is far better con-
	    trolled through the system configuration file (see topic 5. FILES).

       -S : Cumulative time mode toggle
	    Starts top with the last remembered 'S' state reversed.  When  'Cumulative	mode'  is
	    On, each process is listed with the cpu time that it and its dead children have used.
	    See the 'S' interactive command for additional information regarding this mode.

       -v : Version
	    Show library version and the usage prompt, then quit.

2. FIELDS / Columns
   2a. DESCRIPTIONS of Fields
       Listed below are top's available fields.  They  are  always  associated	with  the  letter
       shown,  regardless  of  the position you may have established for them with the 'o' (Order
       fields) interactive command.

       Any field is selectable as the sort field, and you control whether they are  sorted  high-
       to-low  or  low-to-high.  For additional information on sort provisions see topic 3c. TASK
       Area Commands.

       a: PID  --  Process Id
	  The task's unique process ID, which periodically  wraps,  though  never  restarting  at
	  zero.

       b: PPID	--  Parent Process Pid
	  The process ID of a task's parent.

       c: RUSER  --  Real User Name
	  The real user name of the task's owner.

       d: UID  --  User Id
	  The effective user ID of the task's owner.

       e: USER	--  User Name
	  The effective user name of the task's owner.

       f: GROUP  --  Group Name
	  The effective group name of the task's owner.

       g: TTY  --  Controlling Tty
	  The  name  of  the controlling terminal.  This is usually the device (serial port, pty,
	  etc.) from which the process was started, and which it uses for input or output.   How-
	  ever,  a task need not be associated with a terminal, in which case you'll see '?' dis-
	  played.

       h: PR  --  Priority
	  The priority of the task.

       i: NI  --  Nice value
	  The nice value of the task.  A negative nice value means  higher  priority,  whereas	a
	  positive  nice  value  means	lower priority.  Zero in this field simply means priority
	  will not be adjusted in determining a task's dispatchability.

       j: P  --  Last used CPU (SMP)
	  A number representing the last used processor.  In a true  SMP  environment  this  will
	  likely  change frequently since the kernel intentionally uses weak affinity.	Also, the
	  very act of running top may break this weak affinity and cause more processes to change
	  CPUs more often (because of the extra demand for cpu time).

       k: %CPU	--  CPU usage
	  The  task's  share of the elapsed CPU time since the last screen update, expressed as a
	  percentage of total CPU time.  In a true SMP environment, if 'Irix mode'  is	Off,  top
	  will	operate  in  'Solaris mode' where a task's cpu usage will be divided by the total
	  number of CPUs.  You toggle 'Irix/Solaris' modes with the 'I' interactive command.

       l: TIME	--  CPU Time
	  Total CPU time the task has used since it started.  When 'Cumulative mode' is On,  each
	  process is listed with the cpu time that it and its dead children has used.  You toggle
	  'Cumulative mode' with 'S', which is a command-line option and an interactive  command.
	  See the 'S' interactive command for additional information regarding this mode.

       m: TIME+  --  CPU Time, hundredths
	  The same as 'TIME', but reflecting more granularity through hundredths of a second.

       n: %MEM	--  Memory usage (RES)
	  A task's currently used share of available physical memory.

       o: VIRT	--  Virtual Image (kb)
	  The  total  amount  of virtual memory used by the task.  It includes all code, data and
	  shared libraries plus pages that have been swapped out and pages that have been  mapped
	  but not used.

       p: SWAP	--  Swapped size (kb)
	  Memory  that	is  not  resident but is present in a task.  This is memory that has been
	  swapped out but could include additional non-resident memory.  This  column  is  calcu-
	  lated by subtracting physical memory from virtual memory.

       q: RES  --  Resident size (kb)
	  The non-swapped physical memory a task has used.

       r: CODE	--  Code size (kb)
	  The  amount of virtual memory devoted to executable code, also known as the 'text resi-
	  dent set' size or TRS.

       s: DATA	--  Data+Stack size (kb)
	  The amount of virtual memory devoted to other than executable code, also known  as  the
	  'data resident set' size or DRS.

       t: SHR  --  Shared Mem size (kb)
	  The  amount  of  shared memory used by a task.  It simply reflects memory that could be
	  potentially shared with other processes.

       u: nFLT	--  Page Fault count
	  The number of major page faults that have occurred for a task.   A  page  fault  occurs
	  when	a  process attempts to read from or write to a virtual page that is not currently
	  present in its address space.  A major page fault is when backing storage access  (such
	  as a disk) is involved in making that page available.

       v: nDRT	--  Dirty Pages count
	  The  number  of  pages  that	have  been modified since they were last written to disk.
	  Dirty pages must be written to disk before the corresponding physical  memory  location
	  can be used for some other virtual page.

       w: S  --  Process Status
	  The status of the task which can be one of:
	     'D' = uninterruptible sleep
	     'R' = running
	     'S' = sleeping
	     'T' = traced or stopped
	     'Z' = zombie

	  Tasks  shown as running should be more properly thought of as 'ready to run'	--  their
	  task_struct is simply represented on the Linux run-queue.   Even  without  a	true  SMP
	  machine, you may see numerous tasks in this state depending on top's delay interval and
	  nice value.

       x: Command  --  Command line or Program name
	  Display the command line used to start a task or the name of	the  associated  program.
	  You  toggle between command line and name with 'c', which is both a command-line option
	  and an interactive command.

	  When you've chosen to display command lines, processes without  a  command  line  (like
	  kernel  threads)  will  be  shown with only the program name in parentheses, as in this
	  example:
		( mdrecoveryd )

	  Either form of display is subject to potential truncation if it's too long  to  fit  in
	  this field's current width.  That width depends upon other fields selected, their order
	  and the current screen width.

	  Note: The 'Command' field/column is unique, in that it is not fixed-width.   When  dis-
	  played, this column will be allocated all remaining screen width (up to the maximum 512
	  characters) to provide for the potential growth of program names into command lines.

       y: WCHAN  --  Sleeping in Function
	  Depending on the availability of the kernel link map ('System.map'),	this  field  will
	  show	the  name  or  the  address of the kernel function in which the task is currently
	  sleeping.  Running tasks will display a dash ('-') in this column.

	  Note: By displaying this field, top's own working set will be increased by over  700Kb.
	  Your only means of reducing that overhead will be to stop and restart top.

       z: Flags  --  Task Flags
	  This column represents the task's current scheduling flags which are expressed in hexa-
	  decimal notation and with zeros suppressed.  These flags are officially  documented  in
	  <linux/sched.h>.   Less  formal  documentation can also be found on the 'Fields select'
	  and 'Order fields' screens.

   2b. SELECTING and ORDERING Columns
       After pressing the interactive commands 'f' (Fields select) or 'o' (Order fields) you will
       be  shown a screen containing the current fields string followed by names and descriptions
       for all fields.

       Here is a sample fields string from one of top's four windows/field groups and an explana-
       tion of the conventions used:

       -  Sample fields string:
	     ANOPQRSTUVXbcdefgjlmyzWHIK

       -  The order of displayed fields corresponds to the order of the letters in that string.

       -  If  the  letter is upper case the corresponding field itself will then be shown as part
	  of the task display (screen width permitting).  This will also be indicated by a  lead-
	  ing asterisk ('*'), as in this excerpt:
	      ...
	      * K: %CPU       = CPU usage
		l: TIME       = CPU Time
		m: TIME+      = CPU Time, hundredths
	      * N: %MEM       = Memory usage (RES)
	      * O: VIRT       = Virtual Image (kb)
	      ...

       Fields select screen  --  the 'f' interactive command
	  You toggle the display of a field by simply pressing the corresponding letter.

       Order fields screen  --	the 'o' interactive command
	  You move a field to the left by pressing the corresponding upper case letter and to the
	  right with the lower case letter.

   2c. CPU States
       The CPU states are shown in the Summary Area. They are always shown as  a  percentage  and
       are for the time between now and the last refresh.

	us  --	User CPU time
	  The time the CPU has spent running users' processes that are not niced.

	sy  --	System CPU time
	  The time the CPU has spent running the kernel and its processes.

	ni  --	Nice CPU time
	  The time the CPU has spent running users' proccess that have been niced.

	wa  --	iowait
	  Amount of time the CPU has been waiting for I/O to complete.

	hi  --	Hardware IRQ
	  The amount of time the CPU has been servicing hardware interrupts.

	si  --	Software Interrupts
	  The amount of time the CPU has been servicing software interrupts.

	st  --	Steal Time
	  The  amount of CPU 'stolen' from this virtual machine by the hypervisor for other tasks
	  (such as running another virtual machine).

3. INTERACTIVE Commands
       Listed below is a brief index of commands within categories.  Some  commands  appear  more
       than  once  --  their meaning or scope may vary depending on the context in which they are
       issued.

	 3a. GLOBAL_Commands
	       <Ret/Sp> ?, =, A, B, d, G, h, I, k, q, r, s, W, Z
	 3b. SUMMARY_Area_Commands
	       l, m, t, 1
	 3c. TASK_Area_Commands
	       Appearance:  b, x, y, z
	       Content:     c, f, H, o, S, u
	       Size:	    #, i, n
	       Sorting:     <, >, F, O, R
	 3d. COLOR_Mapping
	       <Ret>, a, B, b, H, M, q, S, T, w, z, 0 - 7
	 4b. COMMANDS_for_Windows
	       -, _, =, +, A, a, G, g, w

   3a. GLOBAL Commands
       The global interactive commands are always available in both full-screen mode  and  alter-
       nate-display  mode.   However,  some  of these interactive commands are not available when
       running in 'Secure mode'.

       If you wish to know in advance whether or not your top has been secured,  simply  ask  for
       help and view the system summary on the second line.

	 <Enter> or <Space> :Refresh_Display
	      These  commands do nothing, they are simply ignored.  However, they will awaken top
	      and following receipt of any input the entire display will be repainted.

	      Use either of these keys if you have a large delay interval and wish to see current
	      status,

	 <?> or <h> :Help
	      There  are two help levels available.  The first will provide a reminder of all the
	      basic interactive commands.  If top is secured, that screen will be abbreviated.

	      Typing 'h' or '?' on that help screen will take you to help for  those  interactive
	      commands applicable to alternate-display mode.

	 <=> :Exit_Task_Limits
	      Removes  restrictions  on which tasks are shown.	This command will reverse any 'i'
	      (idle tasks) and 'n' (max tasks) commands that might be active.  It  also  provides
	      for  an 'exit' from PID monitoring.  See the '-p' command-line option for a discus-
	      sion of PID monitoring.

	      When operating in alternate-display mode this command has a slightly broader  mean-
	      ing.

	 <A> :Alternate_Display_Mode_toggle
	      This  command will switch between full-screen mode and alternate-display mode.  See
	      topic 4. ALTERNATE-DISPLAY Mode and the 'G' interactive command  for  insight  into
	      'current' windows and field groups.

	 <B> :Bold_Disable/Enable_toggle
	      This  command  will influence use of the 'bold' terminfo capability and alters both
	      the summary area and task area for the 'current' window.	While it is intended pri-
	      marily for use with dumb terminals, it can be applied anytime.

	      Note:  When  this  toggle is On and top is operating in monochrome mode, the entire
	      display will appear as normal text.  Thus, unless the 'x' and/or	'y'  toggles  are
	      using reverse for emphasis, there will be no visual confirmation that they are even
	      on.

       * <d> or <s> :Change_Delay_Time_interval
	      You will be prompted to enter the delay time, in seconds, between display updates.

	      Fractional seconds are honored, but a negative number is not allowed.   Entering	0
	      causes  (nearly)	continuous  updates, with an unsatisfactory display as the system
	      and tty driver try to keep up with top's demands.  The  delay  value  is	inversely
	      proportional to system loading, so set it with care.

	      If  at  any  time  you wish to know the current delay time, simply ask for help and
	      view the system summary on the second line.

	 <G> :Choose_Another_Window/Field_Group
	      You will be prompted to enter a number between 1 and 4 designating the window/field
	      group  which  should  be made the 'current' window.  You will soon grow comfortable
	      with these 4 windows, especially after experimenting with alternate-display mode.

	 <I> :Irix/Solaris_Mode_toggle
	      When operating in 'Solaris mode' ('I' toggled Off), a  task's  cpu  usage  will  be
	      divided  by  the	total  number  of  CPUs.   After  issuing this command, you'll be
	      informed of the new state of this toggle.

	 <u> :select a user
	      You will be prompted for a  UID  or  username.  Only  processes  belonging  to  the
	      selected user will be displayed. This option matches on the effective UID.

	 <U> :select a user
	      You  will  be  prompted  for  a  UID  or	username. Only processes belonging to the
	      selected user will be displayed. This option matches on the real, effective, saved,
	      and filesystem UID.

       * <k> :Kill_a_task
	      You will be prompted for a PID and then the signal to send.  The default signal, as
	      reflected in the prompt, is SIGTERM.  However, you can send any signal, via  number
	      or name.

	      If  you  wish  to abort the kill process, do one of the following depending on your
	      progress:
		 1) at the pid prompt, just press <Enter>
		 2) at the signal prompt, type 0

	 <q> :Quit

       * <r> :Renice_a_Task
	      You will be prompted for a PID and then the value to nice it to.	Entering a  posi-
	      tive  value  will  cause	a process to lose priority.  Conversely, a negative value
	      will cause a process to be viewed more favorably by the kernel.

	 <W> :Write_the_Configuration_File
	      This will save all of your options and toggles plus the current  display	mode  and
	      delay  time.   By  issuing  this command just before quitting top, you will be able
	      restart later in exactly that same state.

	 <Z> :Change_Color_Mapping
	      This key will take you to a separate screen where you can change the colors for the
	      'current'  window, or for all windows.  For details regarding this interactive com-
	      mand see topic 3d. COLOR Mapping.

       *  The commands shown with an asterisk ('*') are not available in 'Secure mode', nor  will
	  they be shown on the level-1 help screen.

   3b. SUMMARY Area Commands
       The  summary  area  interactive commands are always available in both full-screen mode and
       alternate-display mode.	They affect the beginning lines of your display and  will  deter-
       mine the position of messages and prompts.

       These  commands	always impact just the 'current' window/field group.  See topic 4. ALTER-
       NATE-DISPLAY Mode and the 'G' interactive command for insight into 'current'  windows  and
       field groups.

	 <l> :Toggle_Load_Average/Uptime  --  On/Off
	      This  is also the line containing the program name (possibly an alias) when operat-
	      ing in full-screen mode or the 'current'	window	name  when  operating  in  alter-
	      nate-display mode.

	 <m> :Toggle_Memory/Swap_Usage	--  On/Off
	      This command affects two summary area lines.

	 <t> :Toggle_Task/Cpu_States  --  On/Off
	      This  command  affects from 2 to many summary area lines, depending on the state of
	      the '1' toggle and whether or not top is running under true SMP.

	 <1> :Toggle_Single/Separate_Cpu_States  --  On/Off
	      This command affects how the 't' command's Cpu States portion is	shown.	 Although
	      this  toggle  exists  primarily to serve massively-parallel SMP machines, it is not
	      restricted to solely SMP environments.

	      When you see 'Cpu(s):' in the summary area, the '1' toggle is On and all cpu infor-
	      mation  is  gathered in a single line.  Otherwise, each cpu is displayed separately
	      as: 'Cpu0, Cpu1, ...'

       Note: If the entire summary area has been toggled Off for any window, you  would  be  left
       with  just the message line.  In that way, you will have maximized available task rows but
       (temporarily) sacrificed the program name in full-screen mode or the 'current' window name
       when in alternate-display mode.

   3c. TASK Area Commands
       The task area interactive commands are always available in full-screen mode.

       The  task  area	interactive commands are never available in alternate-display mode if the
       'current' window's task display has been  toggled  Off  (see  topic  4.	ALTERNATE-DISPLAY
       Mode).

       APPEARANCE of task window
	 The following commands will also be influenced by the state of the global 'B' (bold dis-
	 able) toggle.

	 <b> :Bold/Reverse_toggle
	      This command will impact how the 'x' and 'y' toggles are	displayed.   Further,  it
	      will only be available when at least one of those toggles is On.

	 <x> :Column_Highlight_toggle
	      Changes  highlighting  for  the current sort field.  You probably don't need a con-
	      stant visual reminder of the sort field and top hopes  that  you	always	run  with
	      'column highlight' Off, due to the cost in path-length.

	      If  you forget which field is being sorted this command can serve as a quick visual
	      reminder.

	 <y> :Row_Highlight_toggle
	      Changes highlighting for "running" tasks.  For additional insight  into  this  task
	      state, see topic 2a. DESCRIPTIONS of Fields, Process Status.

	      Use  of  this  provision provides important insight into your system's health.  The
	      only costs will be a few additional tty escape sequences.

	 <z> :Color/Monochrome_toggle
	      Switches the 'current' window between your last used color  scheme  and  the  older
	      form of black-on-white or white-on-black.  This command will alter both the summary
	      area and task area but does not affect the state of the 'x', 'y' or 'b' toggles.

       CONTENT of task window
	 <c> :Command_Line/Program_Name_toggle
	      This command will be honored whether or not the 'Command' column is currently visi-
	      ble.  Later, should that field come into view, the change you applied will be seen.

	 <f> and <o> :Fields_select or Order_fields
	      These keys display separate screens where you can change which fields are displayed
	      and their order.	For additional information  on	these  interactive  commands  see
	      topic 2b. SELECTING and ORDERING Columns.

	 <S> :Cumulative_Time_Mode_toggle
	      When  this  toggle is On, all individual threads will be displayed.  Otherwise, top
	      displays a summation of all threads in a process.

	 'S' :Cumulative_Time_Mode_toggle
	      When 'Cumulative mode' is On, each process is listed with the cpu time that it  and
	      its dead children have used.

	      When  Off,  programs that fork into many separate tasks will appear less demanding.
	      For programs like 'init' or a shell this is appropriate but for others,  like  com-
	      pilers,  perhaps not.  Experiment with two task windows sharing the same sort field
	      but with different 'S' states and see which representation you prefer.

	      After issuing this command, you'll be informed of the new state of this toggle.  If
	      you  wish  to know in advance whether or not 'Cumulative mode' is in effect, simply
	      ask for help and view the window summary on the second line.

	 <u> :Show_Specific_User_Only
	      You will be prompted to enter the name of the user to display.  Thereafter, in that
	      task  window  only  matching  User ID's will be shown, or possibly no tasks will be
	      shown.

	      Later, if you wish to monitor all tasks again, re-issue this command but just press
	      <Enter> at the prompt, without providing a name.

       SIZE of task window
	 <i> :Idle_Processes_toggle
	      Displays all tasks or just active tasks.	When this toggle is Off, idled or zombied
	      processes will not be displayed.

	      If this command is applied to the last task display when in alternate-display mode,
	      then  it	will  not  affect the window's size, as all prior task displays will have
	      already been painted.

	 <n> or <#> :Set_Maximum_Tasks
	      You will be prompted to enter the number of tasks to display.  The lessor  of  your
	      number and available screen rows will be used.

	      When  used  in  alternate-display  mode, this is the command that gives you precise
	      control over the size of each currently visible task display, except for	the  very
	      last.   It  will not affect the last window's size, as all prior task displays will
	      have already been painted.

	      Note: If you wish to increase the size of the last visible  task	display  when  in
	      alternate-display mode, simply decrease the size of the task display(s) above it.

       SORTING of task window
	 For  compatibility,  this  top supports most of the former top sort keys.  Since this is
	 primarily a service to former top users, these  commands  do  not  appear  on	any  help
	 screen.
	    command   sorted field		    supported
	      A 	start time (non-display)      No
	      M 	%MEM			      Yes
	      N 	PID			      Yes
	      P 	%CPU			      Yes
	      T 	TIME+			      Yes

	 Before  using	any  of  the following sort provisions, top suggests that you temporarily
	 turn on column highlighting using the 'x' interactive command.  That  will  help  ensure
	 that the actual sort environment matches your intent.

	 The  following  interactive commands will only be honored when the current sort field is
	 visible.  The sort field might not be visible because:
	      1) there is insufficient Screen Width
	      2) the 'f' interactive command turned it Off

	 <<> :Move_Sort_Field_Left
	      Moves the sort column to the left unless the current sort field is the first  field
	      being displayed.

	 <>> :Move_Sort_Field_Right
	      Moves  the sort column to the right unless the current sort field is the last field
	      being displayed.

	 The following interactive commands will always be honored whether  or	not  the  current
	 sort field is visible.

	 <F> or <O> :Select_Sort_Field
	      These  keys  display  a separate screen where you can change which field is used as
	      the sort column.

	      If a field is selected which was not previously being displayed, it will be  forced
	      On  when	you return to the top display.	However, depending upon your screen width
	      and the order of your fields, this sort field may not be displayable.

	      This interactive command can be a convenient way to simply verify the current  sort
	      field, when running top with column highlighting turned Off.

	 <R> :Reverse/Normal_Sort_Field_toggle
	      Using  this  interactive	command you can alternate between high-to-low and low-to-
	      high sorts.

	 Note: Field sorting uses internal values, not those in column display.   Thus,  the  TTY
	 and WCHAN fields will violate strict ASCII collating sequence.

   3d. COLOR Mapping
       When  you issue the 'Z' interactive command, you will be presented with a separate screen.
       That screen can be used to change the colors in just the 'current' window or in	all  four
       windows before returning to the top display.

       Available interactive commands
	   4 upper case letters to select a target
	   8 numbers to select a color
	   normal toggles available
	       'B'	 :bold disable/enable
	       'b'	 :running tasks "bold"/reverse
	       'z'	 :color/mono
	   other commands available
	       'a'/'w'	 :apply, then go to next/prior
	       <Enter>	 :apply and exit
	       'q'	 :abandon current changes and exit

       If  your  use  'a'  or  'w'  to cycle the targeted window, you will have applied the color
       scheme that was displayed when you left that window.  You can, of course, easily return to
       any window and reapply different colors or turn colors Off completely with the 'z' toggle.

       The  Color  Mapping  screen can also be used to change the 'current' window/field group in
       either full-screen mode or alternate-display mode.  Whatever  was  targeted  when  'q'  or
       <Enter> was pressed will be made current as you return to the top display.

4. ALTERNATE-DISPLAY Mode
   4a. WINDOWS Overview
       Field Groups/Windows:
	      In  full-screen  mode  there  is	a single window represented by the entire screen.
	      That single window can still be changed to display 1 of 4  different  field  groups
	      (see  the 'G' interactive command, repeated below).  Each of the 4 field groups has
	      a unique separately configurable summary area and its own configurable task area.

	      In alternate-display mode, those 4 underlying field groups can now be made  visible
	      simultaneously, or can be turned Off individually at your command.

	      The  summary  area  will	always exist, even if it's only the message line.  At any
	      given time only one summary area can be displayed.  However, depending on your com-
	      mands, there could be from zero to four separate task displays currently showing on
	      the screen.

       Current Window:
	      The 'current' window is the window associated with the summary area and the  window
	      to  which  task  related	commands are always directed.  Since in alternate-display
	      mode you can toggle the task display Off, some commands might be restricted for the
	      'current' window.

	      A  further  complication	arises	when you have toggled the first summary area line
	      Off.  With the loss of the window name (the 'l' toggled line),  you'll  not  easily
	      know what window is the 'current' window.

   4b. COMMANDS for Windows
	 <-> and <_> :Show/Hide_Window(s)_toggles
	      The  '-'	key  turns the 'current' window's task display On and Off.  When On, that
	      task area will show a minimum of the columns header you've established with the 'f'
	      and  'o' commands.  It will also reflect any other task area options/toggles you've
	      applied yielding zero or more tasks.

	      The '_' key does the same for all task  displays.   In  other  words,  it  switches
	      between  the currently visible task display(s) and any task display(s) you had tog-
	      gled Off.  If all 4 task displays are currently visible, this  interactive  command
	      will leave the summary area as the only display element.

       * <=> and <+> :Equalize_(re-balance)_Window(s)
	      The  '='	key  forces  the  'current' window's task display to be visible.  It also
	      reverses any 'i' (idle tasks) and 'n' (max tasks) commands that might be active.

	      The '+' key does the same for all windows.  The four task displays  will	reappear,
	      evenly  balanced.   They	will also have retained any customizations you had previ-
	      ously applied, except for the 'i' (idle tasks) and 'n' (max tasks) commands.

       * <A> :Alternate_Display_Mode_toggle
	      This command will switch between full-screen mode and alternate-display mode.

	      The first time you issue this command,  all  four  task  displays  will  be  shown.
	      Thereafter when you switch modes, you will see only the task display(s) you've cho-
	      sen to make visible.

       * <a> and <w> :Next_Window_Forward/Backward
	      This will change the 'current' window, which in turn changes the	window	to  which
	      commands	are  directed.	These keys act in a circular fashion so you can reach any
	      desired 'current' window using either key.

	      Assuming the window name is visible (you have not toggled 'l'  Off),  whenever  the
	      'current'  window name loses its emphasis/color, that's a reminder the task display
	      is Off and many commands will be restricted.

       * <G> :Choose_Another_Window/Field_Group
	      You will be prompted to enter a number between 1 and 4 designating the window/field
	      group which should be made the 'current' window.

	      In  full-screen  mode, this command is necessary to alter the 'current' window.  In
	      alternate-display mode, it is simply a less convenient alternative to the  'a'  and
	      'w' commands.

	 <g> :Change_Window/Field_Group_Name
	      You will be prompted for a new name to be applied to the 'current' window.  It does
	      not require that the window name be visible (the 'l' toggle to be On).

       *  The interactive commands shown with an asterisk ('*') have use beyond alternate-display
	  mode.
	      '=', 'A', 'G'  are always available
	      'a', 'w'	     act the same when color mapping

5. FILES
   5a. SYSTEM Configuration File
       The presence of this file will influence which version of the 'help' screen is shown to an
       ordinary user.  More importantly, it will limit what ordinary users are allowed to do when
       top is running.	They will not be able to issue the following commands.
	  k	    Kill a task
	  r	    Renice a task
	  d or s    Change delay/sleep interval

       The  system  configuration file is not created by top.  Rather, you create this file manu-
       ally and place it in the /etc directory.  Its name must be 'toprc' and must have no  lead-
       ing '.' (period).  It must have only two lines.

       Here is an example of the contents of /etc/toprc:
	  s	    # line 1: 'secure' mode switch
	  5.0	    # line 2: 'delay'  interval in seconds

   5b. PERSONAL Configuration File
       This  file is written as '$HOME/.your-name-4-top' + 'rc'.  Use the 'W' interactive command
       to create it or update it.

       Here is the general layout:
	  global    # line 1: the program name/alias notation
	    "	    # line 2: id,altscr,irixps,delay,curwin
	  per ea    # line a: winname,fieldscur
	  window    # line b: winflags,sortindx,maxtasks
	    "	    # line c: summclr,msgsclr,headclr,taskclr

       If the $HOME variable is not present, top will try to  write  the  personal  configuration
       file to the current directory, subject to permissions.

6. STUPID TRICKS Sampler
       Many  of these 'tricks' work best when you give top a scheduling boost.	So plan on start-
       ing him with a nice value of -10, assuming you've got the authority.

   6a. Kernel Magic
       For these stupid tricks, top needs full-screen mode.

       -*-  The user interface, through prompts and help, intentionally implies  that  the  delay
	    interval  is  limited to tenths of a second.  However, you're free to set any desired
	    delay.  If you want to see Linux at his scheduling best, try a delay of  .09  seconds
	    or less.

	    For this experiment, under x-windows open an xterm and maximize it.  Then do the fol-
	    lowing:
	      . provide a scheduling boost and tiny delay via:
		  nice -n -10 top -d.09
	      . keep sorted column highlighting Off to minimize
		path length
	      . turn On reverse row highlighting for emphasis
	      . try various sort columns (TIME/MEM work well),
		and normal or reverse sorts to bring the most
		active processes into view

	    What you'll see is a very busy Linux doing what he's always done for you,  but  there
	    was no program available to illustrate this.

       -*-  Under  an  xterm using 'white-on-black' colors, try setting top's task color to black
	    and be sure that task highlighting is set to bold, not reverse.  Then set  the  delay
	    interval to around .3 seconds.

	    After  bringing  the most active processes into view, what you'll see are the ghostly
	    images of just the currently running tasks.

       -*-  Delete the existing rcfile, or create a new symlink.  Start  this  new  version  then
	    type  'T'  (a  secret key, see topic 3c. TASK Area Commands, Sorting) followed by 'W'
	    and 'q'.  Finally, restart the program with -d0 (zero delay).

	    Your display will be refreshed at three times the rate of  the  former  top,  a  300%
	    speed advantage.  As top climbs the TIME ladder, be as patient as you can while spec-
	    ulating on whether or not top will ever reach the top.

   6b. Bouncing Windows
       For these stupid tricks, top needs alternate-display mode.

       -*-  With 3 or 4 task displays visible, pick any window other than the last and turn  idle
	    processes  Off.   Depending on where you applied 'i', sometimes several task displays
	    are bouncing and sometimes it's like an accordion, as top tries his best to  allocate
	    space.

       -*-  Set  each  window's  summary  lines  differently: one with no memory; another with no
	    states; maybe one with nothing at all, just the message line.  Then hold down 'a'  or
	    'w' and watch a variation on bouncing windows  --  hopping windows.

       -*-  Display  all 4 windows and for each, in turn, set idle processes to Off.  You've just
	    entered the "extreme bounce" zone.

   6c. The Big Bird Window
       This stupid trick also requires alternate-display mode.

       -*-  Display all 4 windows and make sure that 1:Def is the 'current' window.   Then,  keep
	    increasing	window	size until the all the other task displays are "pushed out of the
	    nest".

	    When they've all been displaced, toggle between all visible/invisible windows.   Then
	    ponder this:
	       is top fibbing or telling honestly your imposed truth?

7. BUGS
       Send bug reports to:
	  Albert D. Cahalan, <albert@users.sf.net>

8. HISTORY Former top
       The   original	top   was   written   by   Roger   Binns,  based  on  Branko  Lankester's
       <lankeste@fwi.uva.nl> ps program.

       Robert Nation <nation@rocket.sanders.lockheed.com> adapted it for the proc file system.

       Helmut Geyer <Helmut.Geyer@iwr.uni-heidelberg.de> added support for configurable fields.

       Plus many other individuals contributed over the years.

9. AUTHOR
       This entirely new and enhanced replacement was written by:
	  Jim / James C. Warner, <warnerjc@worldnet.att.net>

       With invaluable help from:
	  Albert D. Cahalan, <albert@users.sf.net>
	  Craig Small, <csmall@small.dropbear.id.au>

10. SEE ALSO
       free(1), ps(1), uptime(1), atop(1), slabtop(1), vmstat(8), w(1).

Linux					  September 2002				   TOP(1)
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