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TOP(1)					  User Commands 				   TOP(1)

NAME
       top - display Linux processes

SYNOPSIS
       top -hv|-bcHiOSs -d secs -n max -u|U user -p pid -o fld -w [cols]

       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 processes or threads currently being  man-
       aged  by  the  Linux kernel.  The types of system summary information shown and the types,
       order and size of information displayed for processes 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. SUMMARY Display
	      a. UPTIME and LOAD Averages
	      b. TASK and CPU States
	      c. MEMORY Usage
	   3. FIELDS / Columns Display
	      a. DESCRIPTIONS of Fields
	      b. MANAGING Fields
	   4. INTERACTIVE Commands
	      a. GLOBAL Commands
	      b. SUMMARY AREA Commands
	      c. TASK AREA Commands
		 1. Appearance
		 2. Content
		 3. Size
		 4. Sorting
	      d. COLOR Mapping
	   5. ALTERNATE-DISPLAY Provisions
	      a. WINDOWS Overview
	      b. COMMANDS for Windows
	      c. SCROLLING a Window
	      d. SEARCHING in a Window
	      e. FILTERING in a Window
	   6. FILES
	      a. SYSTEM Configuration File
	      b. PERSONAL Configuration File
	      c. ADDING INSPECT Entries
	   7. STUPID TRICKS Sampler
	      a. Kernel Magic
	      b. Bouncing Windows
	      c. The Big Bird Window
	      d. The Ol' Switcheroo
	   8. BUGS, 9. HISTORY Former top, 10. AUTHOR, 11. SEE Also

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

       When  started  for  the first time, you'll be presented with these traditional elements on
       the main top screen: 1) Summary Area; 2) Fields/Columns Header; 3)  Task  Area.	 Each  of
       these  will  be explored in the sections that follow.  There is also an Input/Message line
       between the Summary Area and Columns Header which needs no further explanation.

       The main top screen is generally quite adaptive to changes in terminal dimensions under X-
       Windows.   Other  top screens may be less so, especially those with static text.  It ulti-
       mately depends, however, on your particular window manager and terminal	emulator.   There
       may  be occasions when their view of terminal size and current contents differs from top's
       view, which is always based on operating system calls.

       Following any re-size operation, if a top screen is corrupted, appears incomplete or  dis-
       ordered,  simply  typing something innocuous like a punctuation character or cursor motion
       key will usually restore it.  In extreme cases, the following  sequence	almost	certainly
       will:
	      key/cmd  objective
	      ^Z       suspend top
	      fg       resume top
	      <Left>   force a screen redraw (if necessary)

       But  if the display is still corrupted, there is one more step you could try.  Insert this
       command after top has been suspended but before resuming it.
	      key/cmd  objective
	      reset    restore your terminal settings

       Note: the width of top's display will be limited to 512 positions.  Displaying all  fields
       requires approximately 250 characters.  Remaining screen width is usually allocated to any
       variable width columns currently visible.  The variable width columns,  such  as  COMMAND,
       are noted in topic 3a. DESCRIPTIONS of Fields.  Actual output width may also be influenced
       by the -w switch, which is discussed in topic 1. COMMAND-LINE Options.

       Lastly, some of top's screens or functions require the use of cursor motion keys like  the
       standard  arrow keys plus the Home, End, PgUp and PgDn keys.  If your terminal or emulator
       does not provide those keys, the following combinations are accepted as alternatives:
	      key      equivalent-key-combinations
	      Up       alt + \	    or	alt + k
	      Down     alt + /	    or	alt + j
	      Left     alt + <	    or	alt + h
	      Right    alt + >	    or	alt + l (lower case L)
	      PgUp     alt + Up     or	alt + ctrl + k
	      PgDn     alt + Down   or	alt + ctrl + j
	      Home     alt + Left   or	alt + ctrl + h
	      End      alt + Right  or	alt + ctrl + l

       The Up and Down arrow keys have special significance when prompted for line  input  termi-
       nated  with the <Enter> key.  Those keys, or their aliases, can be used to retrieve previ-
       ous input lines which can then be edited and re-input.  And there are four additional keys
       available with line oriented input.
	      key      special-significance
	      Up       recall older strings for re-editing
	      Down     recall newer strings or erase entire line
	      Insert   toggle between insert and overtype modes
	      Delete   character removed at cursor, moving others left
	      Home     jump to beginning of input line
	      End      jump to end of input line

   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.
       All are explained in detail in the sections that follow.

	   Global-defaults
	      'A' - Alt display      Off (full-screen)
	    * 'd' - Delay time	     3.0 seconds
	    * 'H' - Threads mode     Off (summarize as tasks)
	      'I' - Irix mode	     On  (no, 'solaris' smp)
	    * 'p' - PID monitoring   Off (show all processes)
	    * 's' - Secure mode      Off (unsecured)
	      'B' - Bold enable      On  (yes, bold globally)
	   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)
	    * 'i' - Idle tasks	     On  (show all tasks)
	      'J' - Num align right  On  (not left justify)
	      'j' - Str align right  Off (not right justify)
	      'R' - Reverse sort     On  (pids high-to-low)
	    * 'S' - Cumulative time  Off (no, dead children)
	    * 'u' - User filter      Off (show euid only)
	    * 'U' - User filter      Off (show any uid)
	      '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|-bcHiOSs -d secs -n max -u|U user -p pid -o fld -w [cols]

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

       -h | -v	:Help/Version
	    Show library version and the usage prompt, then quit.

       -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.t (secs.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 6a. SYSTEM Configuration File.

       -H  :Threads-mode operation
	    Instructs top to display individual threads.  Without this command-line option a sum-
	    mation  of	all threads in each process is shown.  Later this can be changed with the
	    'H' interactive command.

       -i  :Idle-process toggle
	    Starts top with the last remembered 'i' state reversed.  When  this  toggle  is  Off,
	    tasks  that  have  not used any CPU since the last update will not be displayed.  For
	    additional information regarding this toggle see topic 4c. TASK AREA Commands, SIZE.

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

       -o  :Override-sort-field as:  -o fieldname
	    Specifies the name of the field on which tasks will be sorted, independent of what is
	    reflected in the configuration file.  You can prepend a '+' or '-' to the field  name
	    to	also  override the sort direction.  A leading '+' will force sorting high to low,
	    whereas a '-' will ensure a low to high ordering.

	    This option exists primarily to support automated/scripted batch mode operation.

       -O  :Output-field-names
	    This option acts as a form of help for the above -o option.  It  will  cause  top  to
	    print  each  of  the available field names on a separate line, then quit.  Such names
	    are subject to nls translation.

       -p  :Monitor-PIDs mode as:  -pN1 -pN2 ...  or  -pN1,N2,N3 ...
	    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.

	    A pid value of zero will be treated as the process id of the top program itself  once
	    it is running.

	    This is a command-line option only and should you wish to return to normal operation,
	    it is not necessary to quit and restart top  --  just issue any of these  interactive
	    commands: '=', 'u' or 'U'.

	    The 'p', 'u' and 'U' command-line options are mutually exclusive.

       -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 6. FILES).

       -S  :Cumulative-time toggle
	    Starts top with the last remembered 'S' state reversed.  When 'Cumulative time'  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.

       -u | -U	:User-filter-mode as:  -u | -U number or name
	    Display  only  processes  with  a user id or user name matching that given.  The '-u'
	    option matches on  effective user whereas the '-U' option matches on any user  (real,
	    effective, saved, or filesystem).

	    Prepending an exclamation point ('!') to the user id or name instructs top to display
	    only processes with users not matching the one provided.

	    The 'p', 'u' and 'U' command-line options are mutually exclusive.

       -w  :Output-width-override as:  -w [ number ]
	    In 'Batch' mode, when used without an argument top will format output using the  COL-
	    UMNS=  and	LINES=	environment variables, if set.	Otherwise, width will be fixed at
	    the maximum 512 columns.   With  an  argument,  output  width  can	be  decreased  or
	    increased (up to 512) but the number of rows is considered unlimited.

	    In normal display mode, when used without an argument top will attempt to format out-
	    put using the COLUMNS= and LINES= environment variables, if set.  With  an	argument,
	    output  width  can only be decreased, not increased.  Whether using environment vari-
	    ables or an argument with -w, when not in 'Batch' mode actual terminal dimensions can
	    never be exceeded.

	    Note:  Without  the  use of this command-line option, output width is always based on
	    the terminal at which top was invoked whether or not in 'Batch' mode.

2. SUMMARY Display
       Each of the following three areas are individually controlled through one or more interac-
       tive  commands.	 See topic 4b. SUMMARY AREA Commands for additional information regarding
       these provisions.

   2a. UPTIME and LOAD Averages
       This portion consists of a single line containing:
	   program or window name, depending on display mode
	   current time and length of time since last boot
	   total number of users
	   system load avg over the last 1, 5 and 15 minutes

   2b. TASK and CPU States
       This portion consists of a minimum of two lines.  In an SMP environment, additional  lines
       can reflect individual CPU state percentages.

       Line  1	shows  total tasks or threads, depending on the state of the Threads-mode toggle.
       That total is further classified as:
	   running; sleeping; stopped; zombie

       Line 2 shows CPU state percentages based on the interval since the  last  refresh.   Where
       two labels are shown below, those for more recent kernel versions are shown first.
	   us, user    : time running un-niced user processes
	   sy, system  : time running kernel processes
	   ni, nice    : time running niced user processes
	   wa, IO-wait : time waiting for I/O completion
	   hi : time spent servicing hardware interrupts
	   si : time spent servicing software interrupts
	   st : time stolen from this vm by the hypervisor

   2c. MEMORY Usage
       This  portion  consists	of  two lines which may express values in kibibytes (KiB) through
       exbibytes (EiB) depending on the scaling factor enforced with the 'E' interactive command.

       Line 1 reflects physical memory, classified as:
	   total, used, free and buffers

       Line 2 reflects mostly virtual memory, classified as:
	   total, used, free and cached (which is physical memory)

       This table may help in interpreting the scaled values displayed:
	   KiB = kibibyte = 1024 bytes
	   MiB = mebibyte = 1024 KiB = 1,048,576 bytes
	   GiB = gibibyte = 1024 MiB = 1,073,741,824 bytes
	   TiB = tebibyte = 1024 GiB = 1,099,511,627,776 bytes
	   PiB = pebibyte = 1024 TiB = 1,125,899,906,842,624 bytes
	   EiB = exbibyte = 1024 PiB = 1,152,921,504,606,846,976 bytes

3. FIELDS / Columns
   3a. DESCRIPTIONS of Fields
       Listed below are top's available process fields (columns).  They are shown in strict ascii
       alphabetical  order.   You  may	customize their position and whether or not they are dis-
       playable with the 'f' or 'F' (Fields Management) interactive commands.

       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 4c. TASK
       AREA Commands, SORTING.

       The fields related to physical memory or virtual memory reference '(KiB)' as the  default,
       unsuffixed  display  mode.   Such  fields  can, however, be scaled differently via the 'e'
       interactive command.

	1. %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 a process is multi-threaded and top is not operating in
	   Threads mode, amounts greater than 100% may be reported.  You toggle Threads mode with
	   the 'H' interactive command.

	   Also  for  multi-processor  environments,  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.

	2. %MEM  --  Memory Usage (RES)
	   A task's currently used share of available physical memory.

	3. CGROUPS  --	Control Groups
	   The names of the control group(s) to which a process belongs, or '-' if not applicable
	   for that process.

	   Control Groups provide for allocating resources (cpu, memory, network bandwidth, etc.)
	   among installation-defined groups of processes.  They enable fine-grained control over
	   allocating, denying, prioritizing, managing and monitoring those resources.

	   Many different hierarchies of cgroups can exist simultaneously on a	system	and  each
	   hierarchy  is  attached  to	one  or more subsystems.  A subsystem represents a single
	   resource.

	   Note: The 'CGROUPS' field, unlike most columns, is not fixed-width.	 When  displayed,
	   it  plus any other variable width columns will be allocated all remaining screen width
	   (up to the maximum 512 characters).	Even so, such variable width fields  could  still
	   suffer  truncation.	 See  topic  5c. SCROLLING a Window for additional information on
	   accessing any truncated data.

	4. CODE  --  Code Size (KiB)
	   The amount of physical memory devoted to executable code, also known as the 'text res-
	   ident set' size or TRS.

	5. COMMAND  --	Command Name or Command Line
	   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 brackets, as in this exam-
	   ple:
	       [kthreadd]

	   This field may also be impacted by the 'forest view' display mode.  See the 'V' inter-
	   active command for additional information regarding that mode.

	   Note: The 'COMMAND' field, unlike most columns, is not fixed-width.	 When  displayed,
	   it  plus any other variable width columns will be allocated all remaining screen width
	   (up to the maximum 512 characters).	Even so, such variable width fields  could  still
	   suffer  truncation.	 This  is  especially  true for this field when command lines are
	   being displayed (the 'c' interactive command.)  See topic 5c. SCROLLING a  Window  for
	   additional information on accessing any truncated data.

	6. DATA  --  Data + Stack Size (KiB)
	   The amount of physical memory devoted to other than executable code, also known as the
	   'data resident set' size or DRS.

	7. ENVIRON  --	Environment variables
	   Display all of the environment variables, if any, as seen by the respective processes.
	   These  variables will be displayed in their raw native order, not the sorted order you
	   are accustomed to seeing with an unqualified 'set'.

	   Note: The 'ENVIRON' field, unlike most columns, is not fixed-width.	 When  displayed,
	   it  plus any other variable width columns will be allocated all remaining screen width
	   (up to the maximum 512 characters).	Even so, such variable width fields  could  still
	   suffer truncation.  This is especially true for this field.	See topic 5c. SCROLLING a
	   Window for additional information on accessing any truncated data.

	8. Flags  --  Task Flags
	   This column represents the task's current scheduling  flags	which  are  expressed  in
	   hexadecimal notation and with zeros suppressed.  These flags are officially documented
	   in <linux/sched.h>.

	9. GID	--  Group Id
	   The effective group ID.

       10. GROUP  --  Group Name
	   The effective group name.

       11. 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 dispatch-ability.

       12. 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).

       13. PGRP  --  Process Group Id
	   Every  process  is  member of a unique process group which is used for distribution of
	   signals and by terminals to arbitrate requests for their input  and	output.   When	a
	   process  is	created (forked), it becomes a member of the process group of its parent.
	   By convention, this value equals the process ID (see PID) of the  first  member  of	a
	   process group, called the process group leader.

       14. PID	--  Process Id
	   The	task's	unique	process  ID, which periodically wraps, though never restarting at
	   zero.  In kernel terms, it is a dispatchable entity defined by a 'task_struct'.

	   This value may also be used as: a process group ID (see PGRP); a session  ID  for  the
	   session  leader  (see  SID); a thread group ID for the thread group leader (see TGID);
	   and a TTY process group ID for the process group leader (see TPGID).

       15. PPID  --  Parent Process Id
	   The process ID (pid) of a task's parent.

       16. PR  --  Priority
	   The scheduling priority of the task.  If you see 'rt' in this field, it means the task
	   is running under 'real time' scheduling priority.

	   Under linux, real time priority is somewhat misleading since traditionally the operat-
	   ing itself was not preemptible.  And while the 2.6 kernel  can  be  made  mostly  pre-
	   emptible, it is not always so.

       17. RES	--  Resident Memory Size (KiB)
	   The non-swapped physical memory a task has used.

       18. RUID  --  Real User Id
	   The real user ID.

       19. RUSER  --  Real User Name
	   The real user name.

       20. 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.

       21. SHR	--  Shared Memory Size (KiB)
	   The amount of shared memory available to a task, not all of which is  typically  resi-
	   dent.   It  simply  reflects  memory  that could be potentially shared with other pro-
	   cesses.

       22. SID	--  Session Id
	   A session is a collection of process groups (see PGRP),  usually  established  by  the
	   login shell.  A newly forked process joins the session of its creator.  By convention,
	   this value equals the process ID (see PID) of the first member of the session,  called
	   the session leader, which is usually the login shell.

       23. SUID  --  Saved User Id
	   The saved user ID.

       24. SUPGIDS  --	Supplementary Group IDs
	   The	IDs of any supplementary group(s) established at login or inherited from a task's
	   parent.  They are displayed in a comma delimited list.

	   Note: The 'SUPGIDS' field, unlike most columns, is not fixed-width.	 When  displayed,
	   it  plus any other variable width columns will be allocated all remaining screen width
	   (up to the maximum 512 characters).	Even so, such variable width fields  could  still
	   suffer  truncation.	 See  topic  5c. SCROLLING a Window for additional information on
	   accessing any truncated data.

       25. SUPGRPS  --	Supplementary Group Names
	   The names of any supplementary group(s) established	at  login  or  inherited  from	a
	   task's parent.  They are displayed in a comma delimited list.

	   Note:  The  'SUPGRPS' field, unlike most columns, is not fixed-width.  When displayed,
	   it plus any other variable width columns will be allocated all remaining screen  width
	   (up	to  the maximum 512 characters).  Even so, such variable width fields could still
	   suffer truncation.  See topic 5c. SCROLLING a Window  for  additional  information  on
	   accessing any truncated data.

       26. SUSER  --  Saved User Name
	   The saved user name.

       27. SWAP  --  Swapped Size (KiB)
	   The non-resident portion of a task's address space.

       28. TGID  --  Thread Group Id
	   The ID of the thread group to which a task belongs.	It is the PID of the thread group
	   leader.  In kernel terms, it represents those tasks that share an 'mm_struct'.

       29. 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 have used.  You tog-
	   gle 'Cumulative mode' with 'S', which is both a command-line option and an interactive
	   command.   See  the	'S' interactive command for additional information regarding this
	   mode.

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

       31. TPGID  --  Tty Process Group Id
	   The process group ID of the foreground process for the  connected  tty,  or	-1  if	a
	   process  is not connected to a terminal.  By convention, this value equals the process
	   ID (see PID) of the process group leader (see PGRP).

       32. 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.

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

       34. USED  --  Memory in Use (KiB)
	   This  field	represents the non-swapped physical memory a task has used (RES) plus the
	   non-resident portion of its address space (SWAP).

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

       36. VIRT  --  Virtual Memory Size (KiB)
	   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.

       37. 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.

	   By displaying this field, top's own working set could  be  increased  by  over  700Kb,
	   depending  on the kernel version.  Should that occur, your only means of reducing that
	   overhead will be to stop and restart top.

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

       39. nMaj  --  Major 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 auxiliary storage access  is
	   involved in making that page available.

       40. nMin  --  Minor Page Fault count
	   The	number	of  minor 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 minor page fault does not involve auxiliary storage
	   access in making that page available.

       41. nTH	--  Number of Threads
	   The number of threads associated with a process.

       42. nsIPC  --  IPC namespace
	   The Inode of the namespace used to isolate interprocess communication (IPC)	resources
	   such as System V IPC objects and POSIX message queues.

       43. nsMNT  --  MNT namespace
	   The	Inode of the namespace used to isolate filesystem mount points thus offering dif-
	   ferent views of the filesystem hierarchy.

       44. nsNET  --  NET namespace
	   The Inode of the namespace used to isolate  resources  such	as  network  devices,  IP
	   addresses, IP routing, port numbers, etc.

       45. nsPID  --  PID namespace
	   The	Inode  of  the namespace used to isolate process ID numbers meaning they need not
	   remain unique.  Thus, each such namespace could have its own 'init' (PID #1) to manage
	   various initialization tasks and reap orphaned child processes.

       46. nsUSER  --  USER namespace
	   The	Inode  of  the	namespace used to isolate the user and group ID numbers.  Thus, a
	   process could have a normal unprivileged user ID outside a user namespace while having
	   a user ID of 0, with full root privileges, inside that namespace.

       47. nsUTS  --  UTS namespace
	   The	Inode  of the namespace used to isolate hostname and NIS domain name.  UTS simply
	   means "UNIX Time-sharing System".

       48. vMj	--  Major Page Fault Count Delta
	   The number of major page faults that have occurred since the last update (see nMaj).

       49. vMn	--  Minor Page Fault Count Delta
	   The number of minor page faults that have occurred since the last update (see nMin).

   3b. MANAGING Fields
       After pressing the interactive command 'f' or 'F' (Fields Management)  you  will  be  pre-
       sented  with a screen showing: 1) the 'current' window name; 2) the designated sort field;
       3) all fields in their current order along with	descriptions.	Entries  marked  with  an
       asterisk are the currently displayed fields, screen width permitting.

	   o  As  the  on screen instructions indicate, you navigate among the fields with the Up
	      and Down arrow keys.  The PgUp, PgDn, Home and End keys can also be used to quickly
	      reach the first or last available field.

	   o  The Right arrow key selects a field for repositioning and the Left arrow key or the
	      <Enter> key commits that field's placement.

	   o  The 'd' key or the <Space> bar toggles a field's display status, and thus the pres-
	      ence or absence of the asterisk.

	   o  The  's'	key  designates  a field as the sort field.  See topic 4c. TASK AREA Com-
	      mands, SORTING for additional information regarding your selection of a sort field.

	   o  The 'a' and 'w' keys can be used to cycle through all available windows and the 'q'
	      or <Esc> keys exit Fields Management.

       The  Fields  Management 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
       <Esc>  was  pressed  will  be made current as you return to the top display.  See topic 5.
       ALTERNATE-DISPLAY Provisions and the 'g' interactive command for  insight  into	'current'
       windows and field groups.

       Note:  Any  window  that has been scrolled horizontally will be reset if any field changes
       are made via the Fields Management screen.  Any vertical scrolled position, however,  will
       not  be	affected.   See topic 5c. SCROLLING a Window for additional information regarding
       vertical and horizontal scrolling.

4. 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.

	 4a. Global-Commands
	       <Ent/Sp> ?, =, 0,
	       A, B, d, E, e, g, h, H, I, k, q, r, s, W, X, Y, Z
	 4b. Summary-Area-Commands
	       C, l, t, m, 1, 2, 3
	 4c. Task-Area-Commands
	       Appearance:  b, J, j, x, y, z
	       Content:     c, f, F, o, O, S, u, U, V
	       Size:	    #, i, n
	       Sorting:     <, >, f, F, R
	 4d. Color-Mapping
	       <Ret>, a, B, b, H, M, q, S, T, w, z, 0 - 7
	 5b. Commands-for-Windows
	       -, _, =, +, A, a, g, G, w
	 5c. Scrolling-a-Window
	       C, Up, Dn, Left, Right, PgUp, PgDn, Home, End
	 5d. Searching-in-a-Window
	       L, &

   4a. 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  awaken  top  and following receipt of any input the entire display
	      will be repainted.  They also force an update of any  hotplugged	cpu  or  physical
	      memory changes.

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

	  ? | 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, 'user' filtering and 'other' filtering.	 See  the
	      '-p'  command-line option for a discussion of PID monitoring, the 'U' or 'u' inter-
	      active commands for user filtering and the 'O'  or  'o'  interactive  commands  for
	      'other' filtering.

	      Additionally,  any  window  that has been scrolled will be reset with this command.
	      See topic 5c. SCROLLING a Window for additional information regarding vertical  and
	      horizontal scrolling.

	      When operating in alternate-display mode this command has a broader meaning.

	  0  :Zero-Suppress toggle
	      This  command  determines  whether  zeros  are  shown or suppressed for many of the
	      fields in a task window.	Fields like UID, GID, NI, PR or P  are	not  affected  by
	      this toggle.

	  A  :Alternate-Display-Mode toggle
	      This  command will switch between full-screen mode and alternate-display mode.  See
	      topic 5. ALTERNATE-DISPLAY Provisions 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 | 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.

	  E  :Extend-Memory-Scale in Summary Area
	      With this command you can cycle through the available summary area  memory  scaling
	      which  ranges  from  KiB	(kibibytes  or	1,024  bytes)  through	EiB (exbibytes or
	      1,152,921,504,606,846,976 bytes).

	      If you see a '+' between a displayed number and the following label, it means  that
	      top  was	forced	to  truncate some portion of that number.  By raising the scaling
	      factor, such truncation can be avoided.

	  e  :Extend-Memory-Scale in Task Windows
	      With this command you can cycle through the available task  window  memory  scaling
	      which  ranges  from  KiB	(kibibytes  or	1,024  bytes)  through	PiB (pebibytes or
	      1,125,899,906,842,624 bytes).

	      While top will try to honor the selected target  range,  additional  scaling  might
	      still  be  necessary  in order to accommodate current values.  If you wish to see a
	      more homogeneous result in the memory columns, raising the scaling range will  usu-
	      ally  accomplish	that goal.  Raising it too high, however, is likely to produce an
	      all zero result which cannot be suppressed with the '0' interactive command.

	  g  :Choose-Another-Window/Field-Group
	      You will be prompted to enter a number between 1 and 4 designating the 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.

	  H  :Threads-mode toggle
	      When this toggle is On, individual threads will be displayed for all  processes  in
	      all  visible  task  windows.  Otherwise, top displays a summation of all threads in
	      each process.

	  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 told
	      the new state of this toggle.

       *  k  :Kill-a-task
	      You will be prompted for a PID and then the signal to send.

	      Entering no PID or a negative number will be interpreted as the  default	shown  in
	      the  prompt  (the first task displayed).	A PID value of zero means the top program
	      itself.

	      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, type an invalid number
		  2) at the signal prompt, type 0 (or any invalid signal)

	  q  :Quit

       *  r  :Renice-a-Task
	      You will be prompted for a PID and then the value to nice it to.

	      Entering no PID or a negative number will be interpreted as the  default	shown  in
	      the  prompt  (the first task displayed).	A PID value of zero means the top program
	      itself.

	      A positive nice value will cause a process to lose priority.  Conversely,  a  nega-
	      tive nice value will cause a process to be viewed more favorably by the kernel.  As
	      a general rule, ordinary users can only increase the nice value and  are	prevented
	      from lowering it.

	      If  you wish to abort the renice process, do one of the following depending on your
	      progress:
		  1) at the pid prompt, type an invalid number
		  2) at the nice prompt, type <Enter> with no input

	  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.

	  X  :Extra-Fixed-Width
	      Some fields are fixed width and not scalable.  As such, they are subject to trunca-
	      tion which would be indicated by a '+' in the last position.

	      This interactive command can be used to alter the widths of the following fields:

		  field  default    field  default    field  default
		  GID	    5	    GROUP     8       WCHAN    10
		  RUID	    5	    RUSER     8       nsIPC    10
		  SUID	    5	    SUSER     8       nsMNT    10
		  UID	    5	    USER      8       nsNET    10
				    TTY       8       nsPID    10
						      nsUSR    10
						      nsUTS    10

	      You  will be prompted for the amount to be added to the default widths shown above.
	      Entering zero forces a return to those defaults.

	      If you enter a negative number, top will automatically increase the column size  as
	      needed  until  there is no more truncated data.  You can accelerate this process by
	      reducing the delay interval or holding down the <Space> bar.

	      Note: Whether explicitly or automatically increased, the widths  for  these  fields
	      are  never  decreased  by top.  To narrow them you must specify a smaller number or
	      restore the defaults.

	  Y  :Inspect-Other-Output
	      After issuing the 'Y' interactive command, you will be prompted for a  target  PID.
	      Typing  a value or accepting the default results in a separate screen.  That screen
	      can be used to view a variety of files or piped command output while the normal top
	      iterative display is paused.

	      Note:  This interactive command is only fully realized when supporting entries have
	      been manually added to the end of the top configuration file.  For details on  cre-
	      ating those entries, see topic 6c. ADDING INSPECT Entries.

	      Most  of	the keys used to navigate the Inspect feature are reflected in its header
	      prologue.  There are, however, additional keys available once you have  selected	a
	      particular  file	or  command.   They are familiar to anyone who has used the pager
	      'less' and are summarized here for future reference.

		  key	   function
		  '='	   alternate status-line, file or pipeline
		  '/'	   find, equivalent to 'L' locate
		  'n'	   find next, equivalent to '&' locate next
		  <Space>  scroll down, equivalent to <PgDn>
		  'b'	   scroll up, equivalent to <PgUp>
		  'g'	   first line, equivalent to <Home>
		  'G'	   last line, equivalent to <End>

	  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 4d. 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.

   4b. 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 5. ALTER-
       NATE-DISPLAY Provisions and the 'g' interactive command for insight into 'current' windows
       and field groups.

	  C  :Show-scroll-coordinates toggle
	      Toggle an informational message which is displayed whenever the message line is not
	      otherwise being used.  For additional information see topic 5c. SCROLLING a Window.

	  l  :Load-Average/Uptime toggle
	      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.

	  t  :Task/Cpu-States toggle
	      This command affects from 2 to many summary area lines, depending on the	state  of
	      the  '1',  '2'  or '3' command toggles and whether or not top is running under true
	      SMP.

	      This portion of the summary area is also influenced by the 'H' interactive  command
	      toggle, as reflected in the total label which shows either 'Tasks' or 'Threads'.

	  m  :Memory/Swap-Usage toggle
	      This  command  affects the two summary area lines dealing with physical and virtual
	      memory.

	  1  :Single/Separate-Cpu-States toggle
	      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
	      information  is  gathered in a single line.  Otherwise, each cpu is displayed sepa-
	      rately as: '%Cpu0, %Cpu1, ...'  up to available screen height.

	  2  :NUMA-Nodes/Cpu-Summary toggle
	      This command toggles between the '1' command cpu summary display (only) or  a  sum-
	      mary  display  plus the cpu usage statistics for each NUMA Node.	It is only avail-
	      able if a system has the requisite NUMA support.

	  3  :Expand-NUMA-Node
	      You will be invited to enter a number representing a NUMA Node.  Thereafter, a node
	      summary  plus  the  statistics for each cpu in that node will be shown until either
	      the '1' or '2' command toggle is pressed.  This interactive command is only  avail-
	      able if a system has the requisite NUMA support.

       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.

   4c. 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 5. ALTERNATE-DISPLAY Pro-
       visions).

       APPEARANCE of task window
	  J  :Justify-Numeric-Columns toggle
	      Alternates between right-justified (the default) and left-justified  numeric  data.
	      If  the numeric data completely fills the available column, this command toggle may
	      impact the column header only.

	  j  :Justify-Character-Columns toggle
	      Alternates between left-justified (the default) and right-justified character data.
	      If  the  character  data completely fills the available column, this command toggle
	      may impact the column header only.

	 The following commands will also be influenced by the state  of  the  global  'B'  (bold
	 enable) 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.	If  you  forget  which	field  is
	      being  sorted this command can serve as a quick visual reminder, providing the sort
	      field is being displayed.  The sort field might not be visible because:
		  1) there is insufficient Screen Width
		  2) the 'f' interactive command turned it Off

	      Note: Whenever 'Searching' and/or 'Other Filtering' is active in a  window,  column
	      highlighting  is	temporarily  disabled.	 See  the  notes at the end of topics 5d.
	      SEARCHING and 5e. FILTERING for an explanation why.

	  y  :Row-Highlight toggle
	      Changes highlighting for "running" tasks.  For additional insight  into  this  task
	      state, see topic 3a. DESCRIPTIONS of Fields, the 'S' field (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 | F  :Fields-Management
	      These  keys  display  a  separate screen where you can change which fields are dis-
	      played, their order and also designate the sort field.  For additional  information
	      on these interactive commands see topic 3b. MANAGING Fields.

	  o | O  :Other-Filtering
	      You  will  be prompted for the selection criteria which then determines which tasks
	      will be shown in the 'current' window.  Your criteria can be made case sensitive or
	      case  can  be ignored.  And you determine if top should include or exclude matching
	      tasks.

	      See topic 5e. FILTERING in a window for details on  these  and  additional  related
	      interactive commands.

	  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 | U  :Show-Specific-User-Only
	      You  will  be prompted for the uid or name of the user to display.  The '-u' option
	      matches on  effective user whereas the '-U'  option  matches  on	any  user  (real,
	      effective, saved, or filesystem).

	      Thereafter,  in  that task window only matching users will be shown, or possibly no
	      processes will be shown.	Prepending an exclamation point ('!') to the user  id  or
	      name  instructs  top to display only processes with users not matching the one pro-
	      vided.

	      Different task windows can be used to filter different users.  Later, if	you  wish
	      to  monitor all users again in the 'current' window, re-issue this command but just
	      press <Enter> at the prompt.

	  V  :Forest-View-Mode toggle
	      In this mode, processes are reordered according to their parents and the layout  of
	      the  COMMAND column resembles that of a tree.  In forest view mode it is still pos-
	      sible to toggle between program name and command line (see the 'c' interactive com-
	      mand) or between processes and threads (see the 'H' interactive command).

	      Note:  Typing  any  key  affecting the sort order will exit forest view mode in the
	      'current' window.  See topic 4c. TASK AREA Commands,  SORTING  for  information  on
	      those keys.

       SIZE of task window
	  i  :Idle-Process toggle
	      Displays	all tasks or just active tasks.  When this toggle is Off, tasks that have
	      not used any CPU since the last update will not be displayed.  However, due to  the
	      granularity  of  the  %CPU  and TIME+ fields, some processes may still be displayed
	      that appear to have used no CPU.

	      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 | #  :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 | F  :Fields-Management
	      These  keys  display  a separate screen where you can change which field is used as
	      the sort column, among other functions.  This 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.

   4d. 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.

       The following interactive commands are available.
	   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 you 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.

5. ALTERNATE-DISPLAY Provisions
   5a. 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 sep-
	  arately 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 commands,
	  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.

   5b. COMMANDS for Windows
	  - | _  :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'
	      interactive command.  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.

       *  = | +  :Equalize-(reinitialize)-Window(s)
	      The '=' key forces the 'current' window's task display  to  be  visible.	 It  also
	      reverses	any  'i' (idle tasks), 'n' (max tasks), 'u'/'U' (user filter) and 'o'/'O'
	      (other filter) commands that might  be  active.	Also,  if  the	window	had  been
	      scrolled, it will be reset with this command.  See topic 5c. SCROLLING a Window for
	      additional information regarding vertical and horizontal scrolling.

	      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), 'n' (max tasks), 'u'/'U' (user fil-
	      ter), 'o'/'O' (other filter) and scrolling interactive 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 | 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 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 with color mapping
			     and fields management

   5c. SCROLLING a Window
       Typically a task window is a partial view into a systems's total tasks/threads which shows
       only  some  of the available fields/columns.  With these scrolling keys, you can move that
       view vertically or horizontally to reveal any desired task or column.

       Up,PgUp	:Scroll-Tasks
	   Move the view up toward the first task row, until the first task is displayed  at  the
	   top	of the 'current' window.  The Up arrow key moves a single line while PgUp scrolls
	   the entire window.

       Down,PgDn  :Scroll-Tasks
	   Move the view down toward the last task row, until the last task is the only task dis-
	   played  at  the  top  of the 'current' window.  The Down arrow key moves a single line
	   while PgDn scrolls the entire window.

       Left,Right  :Scroll-Columns
	   Move the view of displayable fields horizontally one column at a time.

	   Note: As a reminder, some fields/columns are not fixed-width but allocated all remain-
	   ing screen width when visible.  When scrolling right or left, that feature may produce
	   some unexpected results initially.

	   Additionally, there are special provisions for any variable	width  field  when  posi-
	   tioned  as  the  last displayed field.  Once that field is reached via the right arrow
	   key, and is thus the only column shown, you can continue scrolling horizontally within
	   such a field.  See the 'C' interactive command below for additional information.

       Home  :Jump-to-Home-Position
	   Reposition the display to the un-scrolled coordinates.

       End  :Jump-to-End-Position
	   Reposition  the  display  so  that  the rightmost column reflects the last displayable
	   field and the bottom task row represents the last task.

	   Note: From this position it is still possible to scroll down and right using the arrow
	   keys.   This  is true until a single column and a single task is left as the only dis-
	   play element.

       C  :Show-scroll-coordinates toggle
	   Toggle an informational message which is displayed whenever the message  line  is  not
	   otherwise being used.  That message will take one of two forms depending on whether or
	   not a variable width column has also been scrolled.

	     scroll coordinates: y = n/n (tasks), x = n/n (fields)
	     scroll coordinates: y = n/n (tasks), x = n/n (fields) + nn

	   The coordinates shown as n/n are relative to the upper left corner  of  the	'current'
	   window.   The additional '+ nn' represents the displacement into a variable width col-
	   umn when it has been scrolled horizontally.	Such  displacement  occurs  in	normal	8
	   character tab stop amounts via the right and left arrow keys.

	   y = n/n (tasks)
	       The  first  n  represents  the topmost visible task and is controlled by scrolling
	       keys.  The second n is updated automatically to reflect total tasks.

	   x = n/n (fields)
	       The first n  represents	the  leftmost  displayed  column  and  is  controlled  by
	       scrolling  keys.   The  second  n is the total number of displayable fields and is
	       established with the 'f' interactive command.

       The above interactive commands are always available in full-screen mode but  never  avail-
       able  in  alternate-display  mode  if the 'current' window's task display has been toggled
       Off.

       Note: When any form of filtering is active, you can expect some	slight	aberrations  when
       scrolling  since  not all tasks will be visible.  This is particularly apparent when using
       the Up/Down arrow keys.

   5d. SEARCHING in a Window
       You can use these interactive commands to locate a task row containing a particular value.

       L  :Locate-a-string
	   You will be prompted for the case-sensitive string to locate starting from the current
	   window coordinates.	There are no restrictions on search string content.

	   Searches  are  not limited to values from a single field or column.	All of the values
	   displayed in a task row are allowed in a search string.  You may include spaces,  num-
	   bers, symbols and even forest view artwork.

	   Keying  <Enter>  with no input will effectively disable the '&' key until a new search
	   string is entered.

       &  :Locate-next
	   Assuming a search string has been established, top will attempt  to	locate	the  next
	   occurrence.

       When  a match is found, the current window is repositioned vertically so the task row con-
       taining that string is first.  The scroll coordinates message can provide confirmation  of
       such vertical repositioning (see the 'C' interactive command).  Horizontal scrolling, how-
       ever, is never altered via searching.

       The availability of a matching string will be influenced by the following factors.
	  a. Which fields are displayable from the total available,
	     see topic 3b. MANAGING Fields.
	  b. Scrolling a window vertically and/or horizontally,
	     see topic 5c. SCROLLING a Window.
	  c. The state of the command/command-line toggle,
	     see the 'c' interactive command.
	  d. The stability of the chosen sort column,
	     for example PID is good but %CPU bad.

       If a search fails, restoring the 'current' window home  (unscrolled)  position,	scrolling
       horizontally, displaying command-lines or choosing a more stable sort field could yet pro-
       duce a successful '&' search.

       The above interactive commands are always available in full-screen mode but  never  avail-
       able  in  alternate-display  mode  if the 'current' window's task display has been toggled
       Off.

       Note: Whenever a search key is typed, top will turn column  highlighting  Off  to  prevent
       false  matches  on  internal  non-display  escape  sequences.   Such  highlighting will be
       restored when a window's search string is empty.  See  the  'x'	interactive  command  for
       additional information on sort column highlighting.

   5e. FILTERING in a Window
       You  can  use  the  'Other Filter' feature to establish selection criteria which will then
       determine which tasks are shown in the 'current' window.

       Establishing a filter requires: 1) a field name; 2) an operator; and 3) a selection value,
       as a minimum.  This is the most complex of top's user input requirements so, when you make
       a mistake, command recall will be your friend.  Remember the Up/Down arrow keys	or  their
       aliases when prompted for input.

       Filter Basics
	  .  field names are case sensitive and spelled as in the header
	  .  selection values need not comprise the full displayed field
	  .  a selection is either case insensitive or sensitive to case
	  .  the default is inclusion, prepending '!' denotes exclusions
	  .  multiple selection criteria can be applied to a task window
	  .  inclusion and exclusion criteria can be used simultaneously
	  .  the 1 equality and 2 relational filters can be freely mixed
	  .  separate unique filters are maintained for each task window

       If a field is not turned on or is not currently in view, then your selection criteria will
       not affect the display.	Later, should a filtered field become visible, the selection cri-
       teria will then be applied.

       Keyboard Summary
	 o  :Other-Filter (lower case)
	     You will be prompted to establish a filter that ignores case when matching.

	 O  :Other-Filter (upper case)
	     You will be prompted to establish a case sensitive filter.

	^O  :Show-Active-Filters (Ctrl key + 'o')
	     This can serve as a reminder of which filters are active in the 'current' window.	A
	     summary will be shown on the message line until you press the <Enter> key.

	 =  :Reset-Filtering in current window
	     This clears all of your selection criteria in the 'current'  window.   It	also  has
	     additional impact so please see topic 4a. GLOBAL Commands.

	 +  :Reset-Filtering in all windows
	     This  clears  the	selection  criteria  in  all  windows, assuming you are in alter-
	     nate-display mode.  As with the '=' interactive command, it too has additional  con-
	     sequences so you might wish to see topic 5b. COMMANDS for Windows.

       Input Requirements
	  When	prompted for selection criteria, the data you provide must take one of two forms.
	  There are 3 required pieces of information, with a 4th as optional.  These examples use
	  spaces for clarity but your input generally would not.
		  #1	       #2  #3		   ( required )
		  Field-Name   ?   include-if-value
	       !  Field-Name   ?   exclude-if-value
	       #4				   ( optional )

	  Items  #1,  #3  and  #4 should be self-explanatory.  Item #2 represents both a required
	  delimiter and the operator which must be one of either equality ('=') or relation  ('<'
	  or '>').

	  The  '='  equality  operator	requires  only	a  partial match and that can reduce your
	  'if-value' input requirements.  The '>'  or  '<'  relational	operators  always  employ
	  string comparisons, even with numeric fields.  They are designed to work with a field's
	  default justification and with homogeneous data.  When  some	field's  numeric  amounts
	  have	been  subjected  to scaling while others have not, that data is no longer homoge-
	  neous.

	  If you establish a relational filter and you have  changed  the  default  'Numeric'  or
	  'Character'  justification, that filter is likely to fail.  When a relational filter is
	  applied to a memory field and you have not changed the scaling, it may produce mislead-
	  ing  results.   This	happens, for example, because '100.0m' (MiB) would appear greater
	  than '1.000g' (GiB) when compared as strings.

	  If your filtered results appear suspect, simply altering justification or  scaling  may
	  yet  achieve	the desired objective.	See the 'j', 'J' and 'e' interactive commands for
	  additional information.

       Potential Problems
	  These GROUP filters could produce the exact same results or the second  one  might  not
	  display anything at all, just a blank task window.
	       GROUP=root	 ( only the same results when )
	       GROUP=ROOT	 ( invoked via lower case 'o' )

	  Either of these RES filters might yield inconsistent and/or misleading results, depend-
	  ing on the current memory scaling factor.  Or both filters could produce the exact same
	  results.
	       RES>9999 	 ( only the same results when )
	       !RES<10000	 ( memory scaling is at 'KiB' )

	  This	nMin  filter  illustrates  a  problem unique to scalable fields.  This particular
	  field can display a maximum of 4 digits, beyond which values are  automatically  scaled
	  to  KiB  or above.  So while amounts greater than 9999 exist, they will appear as 2.6m,
	  197k, etc.
	       nMin>9999	 ( always a blank task window )

       Potential Solutions
	  These examples illustrate how 'Other Filtering' can be creatively  applied  to  achieve
	  almost  any  desired	result.   Single quotes are sometimes shown to delimit the spaces
	  which are part of a filter or to represent a request for status (^O)	accurately.   But
	  if you used them with if-values in real life, no matches would be found.

	  Assuming  field  nTH	is displayed, the first filter will result in only multi-threaded
	  processes being shown.  It also reminds us that a trailing space is part of every  dis-
	  played field.  The second filter achieves the exact same results with less typing.
	       !nTH=' 1 '		 ( ' for clarity only )
	       nTH>1			 ( same with less i/p )

	  With	Forest	View  mode active and the COMMAND column in view, this filter effectively
	  collapses child processes so that just 3 levels are shown.
	       !COMMAND='	`- '	 ( ' for clarity only )

	  The final two filters appear as in response to the status request key (^O).	In  real-
	  ity, each filter would have required separate input.	The PR example shows the two con-
	  current filters necessary to display tasks with priorities of 20 or  more,  since  some
	  might  be  negative.	 Then  by  exploiting trailing spaces, the nMin series of filters
	  could achieve the failed '9999' objective discussed above.
	       'PR>20' + '!PR=-'	 ( 2 for right result )
	       '!nMin=0 ' + '!nMin=1 ' + '!nMin=2 ' + '!nMin=3 ' ...

       Note: When 'Other Filtering' is active, top turns column highlighting Off to prevent false
       matches on internal non-display escape sequences.  Such highlighting will be restored when
       a window is no longer subject to filtering.  See the 'x'  interactive  command  for  addi-
       tional information on sort column highlighting.

6. FILES
   6a. 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

   6b. 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
	   global   # line 15: fixed-width incr
	     "	    # any remaining lines are devoted to the
	     "	    # generalized 'inspect' provisions
	     "	    # discussed below

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

   6c. ADDING INSPECT Entries
       To  exploit  the  'Y' interactive command, you must add entries at the end of the top per-
       sonal configuration file.  Such entries simply reflect a file to be read or  command/pipe-
       line to be executed whose results will then be displayed in a separate scrollable, search-
       able window.

       If you don't know the location or name of your top rcfile, use the 'W' interactive command
       to rewrite it and note those details.

       Inspect	entries can be added with a redirected echo or by editing the configuration file.
       Redirecting an echo risks overwriting the rcfile should it replace (>) rather than  append
       (>>)  to  that  file.   Conversely, when using an editor care must be taken not to corrupt
       existing lines, some of which will contain unprintable data or unusual characters.

       Those Inspect entries beginning with a '#' character are ignored, regardless  of  content.
       Otherwise  they	consist of the following 3 elements, each of which must be separated by a
       tab character (thus 2 '\t' total):

	 .type:  literal 'file' or 'pipe'
	 .name:  selection shown on the Inspect screen
	 .fmts:  string representing a path or command

       The two types of Inspect entries are not interchangeable.  Those designated 'file' will be
       accessed  using	fopen  and  must reference a single file in the '.fmts' element.  Entries
       specifying 'pipe' will employ popen, their '.fmts' element could  contain  many	pipelined
       commands and, none can be interactive.

       If  the	file or pipeline represented in your '.fmts' deals with the specific PID input or
       accepted when prompted, then the format string must also contain the  '%d'  specifier,  as
       these examples illustrate.

	 .fmts=  /proc/%d/numa_maps
	 .fmts=  lsof -P -p %d

       For  'pipe'  type  entries only, you may also wish to redirect stderr to stdout for a more
       comprehensive result.  Thus the format string becomes:

	 .fmts=  pmap -x %d 2>&1

       Here are examples of both types of Inspect entries as they might  appear  in  the  rcfile.
       The first entry will be ignored due to the initial '#' character.  For clarity, the pseudo
       tab depictions (^I) are surrounded by an extra space but the actual tabs would not be.

	 # pipe ^I Sockets ^I lsof -n -P -i 2>&1
	 pipe ^I Open Files ^I lsof -P -p %d 2>&1
	 file ^I NUMA Info ^I /proc/%d/numa_maps
	 pipe ^I Log ^I tail -n100 /var/log/syslog | sort -Mr

       Except for the commented entry above, these next examples show what  could  be  echoed  to
       achieve	similar  results,  assuming  the  rcfile  name was '.toprc'.  However, due to the
       embedded tab characters, each of these lines should be preceded	by  '/bin/echo	-e',  not
       just  a simple an 'echo', to enable backslash interpretation regardless of which shell you
       use.

	 "pipe\tOpen Files\tlsof -P -p %d 2>&1" >> ~/.toprc
	 "file\tNUMA Info\t/proc/%d/numa_maps" >> ~/.toprc
	 "pipe\tLog\ttail -n200 /var/log/syslog | sort -Mr" >> ~/.toprc

       Caution: If any inspect entry you create produces output with unprintable characters  they
       will  be  displayed in either the ^C notation or hexadecimal <FF> form, depending on their
       value.  This applies to tab characters as well, which will show as '^I'.  If  you  want	a
       truer representation, any embedded tabs should be expanded.

	 # next would have contained '\t' ...
	 # file ^I <your_name> ^I /proc/%d/status
	 # but this will eliminate embedded '\t' ...
	 pipe ^I <your_name> ^I cat /proc/%d/status | expand -

       The  above  example takes what could have been a 'file' entry but employs a 'pipe' instead
       so as to expand the embedded tabs.

       Note: While 'pipe' type entries have been discussed in terms of	pipelines  and	commands,
       there is nothing to prevent you from including  shell scripts as well.  Perhaps even newly
       created scripts designed specifically for the 'Y' interactive command.

       Lastly, as the number of your Inspect entries grows over time, the 'Options:' row will  be
       truncated  when	screen	width  is exceeded.  That does not affect operation other than to
       make some selections invisible.

       However, if some choices are lost to truncation but you want to see more options, there is
       an easy solution hinted at below.

	 Inspection Pause at pid ...
	 Use:  left/right then <Enter> ...
	 Options:  help  1  2  3  4  5	6  7  8  9  10	11 ...

       The  entries  in the top rcfile would have a number for the '.name' element and the 'help'
       entry would identify a shell script you've written explaining what those  numbered  selec-
       tions actually mean.  In that way, many more choices can be made visible.

7. 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.

   7a. Kernel Magic
       For these stupid tricks, top needs full-screen mode.

       o  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 so as 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.

       o  Under  an  xterm  using  'white-on-black' colors, on top's Color Mapping screen set the
	  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.

       o  Delete the existing rcfile, or create a new symlink.	Start this new version then  type
	  'T'  (a secret key, see topic 4c. 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 speculating
	  on whether or not top will ever reach the top.

   7b. Bouncing Windows
       For these stupid tricks, top needs alternate-display mode.

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

       o  Set  each window's summary lines differently: one with no memory ('m'); another with no
	  states ('t'); 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.

       o  Display  all	4  windows and for each, in turn, set idle processes to Off using the 'i'
	  command toggle.  You've just entered the "extreme bounce" zone.

   7c. The Big Bird Window
       This stupid trick also requires alternate-display mode.

       o  Display all 4 windows and make sure that 1:Def is the  'current'  window.   Then,  keep
	  increasing  window  size with the 'n' interactive command until all the other task dis-
	  plays are "pushed out of the nest".

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

   7d. The Ol' Switcheroo
       This stupid trick works best without alternate-display mode, since justification is active
       on a per window basis.

       o  Start top and make COMMAND the last (rightmost) column displayed.   If  necessary,  use
	  the  'c'  command  toggle  to display command lines and ensure that forest view mode is
	  active with the 'V' command toggle.

	  Then use the up/down arrow keys to position the display so that some truncated  command
	  lines  are  shown ('+' in last position).  You may have to resize your xterm to produce
	  truncation.

	  Lastly, use the 'j' command toggle to make the COMMAND column right justified.

	  Now use the right arrow key to reach the COMMAND column.   Continuing  with  the  right
	  arrow key, watch closely the direction of travel for the command lines being shown.

	     some lines travel left, while others travel right

	     eventually all lines will Switcheroo, and move right

8. BUGS
       To report bugs, follow the instructions at:
	   http://www.debian.org/Bugs/Reporting

9. 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.

10. AUTHOR
       This entirely new and enhanced replacement was written by:
	   Jim Warner, <james.warner@comcast.net>

       With invaluable help from:
	   Craig Small, <csmall@enc.com.au>
	   Albert Cahalan, <albert@users.sf.net>

11. SEE Also
       free(1), ps(1), uptime(1), atop(1), slabtop(1), vmstat(8), w(1).

procps-ng				  November 2013 				   TOP(1)
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