vztop(1) - display Linux processes



  • VZTOP(1)					      User Commands						VZTOP(1)
    
    
    
    NAME
           vztop - display Linux processes
    
    
    SYNOPSIS
           vztop -hv|-bcHiOSs -E ctid -d secs -n max -u|U user -p pid -o fld -w [cols]
    
    
           The traditional switches `-' and whitespace are optional.
    
    
    DESCRIPTION
           The  vztop program provides a dynamic real-time view of a running system.  It can display system summary informa‐
           tion as well as a list of processes or threads currently being managed 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 con‐
           figurable 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 vztop is
           referred to throughout this document, you are free to name the program anything you wish.  That new name,  possi‐
           bly an alias, will then be reflected on vztop'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 vztop, 10. AUTHOR, 11. SEE Also
    
    
       Operation
           When  operating vztop, 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 vztop screen: 1)
           Summary	Area;  2) Fields/Columns Header; 3) Task Area.	Each of these will be explored in the sections that fol‐
           low.  There is also an Input/Message line between the Summary Area and Columns  Header  which  needs  no	 further
           explanation.
    
           The main vztop screen is generally quite adaptive to changes in terminal dimensions under X-Windows.  Other vztop
           screens may be less so, especially those with static text.  It ultimately depends, however,  on	your  particular
           window  manager	and terminal emulator.	There may be occasions when their view of terminal size and current con‐
           tents differs from vztop's view, which is always based on operating system calls.
    
           Following any re-size operation, if a vztop screen is corrupted, appears incomplete or disordered, 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 vztop
    	      fg       resume vztop
    	      <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 vztop has
           been suspended but before resuming it.
    	      key/cmd  objective
    	      reset    restore your terminal settings
    
           Note:  the  width  of  vztop's display will be limited to 512 positions.	 Displaying all fields requires approxi‐
           mately 250 characters.  Remaining screen width is usually allocated to any variable width columns currently visi‐
           ble.   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 vztop'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  terminated  with  the	 <Enter>
           key.  Those keys, or their aliases, can be used to retrieve previous 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	   1.5 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	   Off (thus multiple cpus)
    	   Task-Area-defaults
    	      b - Bold hilite	   Off (use `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)
    	      V - Forest view	   On  (show as branches)
    	      x - Column hilite	   Off (no, sort field)
    	      y - Row hilite	   On  (yes, running tasks)
    	      z - color/mono	   On  (show colors)
    
    
    1. COMMAND-LINE Options
           The command-line syntax for vztop consists of:
    
    	 -hv|-bcHiOSs -E ctid -d secs -n max -u|U user -p pid -o fld -w [cols]
    
           The typically mandatory switch ('-') and even whitespace are completely optional.
    
    
           -h | -v	:Help/Version
    	    Show library version and the usage prompt, then quit.
    
    
           -D :CTID selection
    	    Select the processes for specified ctid.
    
    
           -b  :Batch-mode operation
    	    Starts vztop in Batch mode, which could be useful for sending output from vztop to other programs  or  to  a
    	    file.   In	this  mode,  vztop 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 vztop with the last remembered `c' state reversed.  Thus, if vztop was displaying command lines,  now
    	    that field will show program names, and visa versa.	 See the `c' interactive command for additional informa‐
    	    tion.
    
    
           -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 configu‐
    	    ration 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 vztop 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  vztop to display individual threads.  Without this command-line option a summation of all threads
    	    in each process is shown.  Later this can be changed with the `H' interactive command.
    
    
           -i  :Idle-process toggle
    	    Starts vztop 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, vztop should produce before ending.
    
    
           -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  con‐
    	    figuration	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 vztop to print each of the avail‐
    	    able 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 pro‐
    	    vide 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 vztop 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 vztop  --	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  vztop with secure mode forced, even for root.  This mode is far better controlled through the system
    	    configuration file (see topic 6. FILES).
    
    
           -S  :Cumulative-time toggle
    	    Starts vztop 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 addi‐
    	    tional 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	  effec‐
    	    tive 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 vztop 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 vztop will format output using the COLUMNS= and LINES= environ‐
    	    ment  variables, if set.  Otherwise, width will be fixed at the maximum 512 columns.  With an argument, out‐
    	    put 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 vztop will attempt to format output using the COLUMNS=
    	    and	 LINES=	 environment  variables,  if  set.   With  an  argument, output width can only be decreased, not
    	    increased.	Whether using environment variables or an argument with -w, when not in Batch mode actual termi‐
    	    nal dimensions can never be exceeded.
    
    	    Note:  Without  the	 use  of this command-line option, output width is always based on the terminal at which
    	    vztop was invoked whether or not in Batch mode.
    
    
    2. SUMMARY Display
           Each of the following three areas are individually controlled through one  or  more  interactive	 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.
    
           As a default, percentages for these individual categories are displayed.	 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
    	   id, idle    : time spent in the kernel idle handler
    	   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
    
           In the alternate cpu states display modes, beyond the first tasks/threads line, an abbreviated summary  is  shown
           consisting of these elements:
    		      a	   b	 c    d
    	   %Cpu(s):  75.0/25.0	100[ ...
    
    
           Where:  a)  is  the combined us and ni percentage; b) is the sy percentage; c) is the total; and d) is one of two
           visual graphs of those representations.	See topic 4b. SUMMARY AREA Commands and the `t' command	 for  additional
           information on that special 4-way toggle.
    
    
       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.
    
           As a default, Line 1 reflects physical memory, classified as:
    	   total, free, used and buff/cache
    
           Line 2 reflects mostly virtual memory, classified as:
    	   total, free, used and avail (which is physical memory)
    
           The avail number on line 2 is an estimation of physical memory available for starting new  applications,	 without
           swapping.  Unlike the free field, it attempts to account for readily reclaimable page cache and memory slabs.  It
           is available on kernels 3.14, emulated on kernels 2.6.27+, otherwise the same as free.
    
           In the alternate memory display modes, two abbreviated summary lines are shown consisting of these elements:
    		      a	   b	      c
    	   GiB Mem : 18.7/15.738   [ ...
    	   GiB Swap:  0.0/7.999	   [ ...
    
           Where: a) is the percentage used; b) is the total available; and c) is one of two visual graphs of  those  repre‐
           sentations.
    
           In  the	case of physical memory, the percentage represents the total minus the estimated avail noted above.  The
           `Mem' graph itself is divided between used and any remaining memory not otherwise accounted for	by  avail.   See
           topic 4b. SUMMARY AREA Commands and the `m' command for additional information on that special 4-way toggle.
    
           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 vztop's available process fields (columns).  They are shown in strict ascii alphabetical order.
           You may customize their position and whether or not they are displayable 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)' which is the unsuffixed  display  mode.
           Such  fields  may,  however,  be scaled from KiB through PiB.  That scaling is influenced via the `e' interactive
           command or established for startup through a build option.
    
    
    	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 vztop 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, vztop 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' interac‐
    	   tive 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, manag‐
    	   ing 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 infor‐
    	   mation on accessing any truncated data.
    
    
    	4. CODE	 --  Code Size (KiB)
    	   The amount of physical memory devoted to executable code, also known as the Text Resident 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 com‐
    	   mand 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 example:
    	       [kthreadd]
    
    	   This field may also be impacted by the forest view display mode.  See the `V' interactive command  for  addi‐
    	   tional 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 dis‐
    	   patch-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 vztop 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 mem‐
    	   ber 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 operating itself was not pre‐
    	   emptible.  And while the 2.6 kernel can be made mostly preemptible, it is not always so.
    
    
           17. RES	--  Resident Memory Size (KiB)
    	   The non-swapped physical memory a task is using.
    
    
           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 = stopped by job control signal
    	       t = stopped by debugger during trace
    	       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 vztop'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 resident.  It simply	reflects
    	   memory that could be potentially shared with other processes.
    
    
           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 dis‐
    	   played 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  infor‐
    	   mation 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  infor‐
    	   mation 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 toggle 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.	However, a task need not be  associated	 with  a
    	   terminal, in which case you'll see `?' displayed.
    
    
           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, vztop'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 vztop.
    
    
           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 different 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 nor‐
    	   mal 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 presented with a  screen  show‐
           ing:  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.
    
    
    	   ·  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.
    
    
    	   ·  The  Right  arrow	 key selects a field for repositioning and the Left arrow key or the <Enter> key commits
    	      that field's placement.
    
    
    	   ·  The `d' key or the <Space> bar toggles a field's display status, and thus the presence or absence	 of  the
    	      asterisk.
    
    
    	   ·  The  `s'	key  designates	 a field as the sort field.  See topic 4c. TASK AREA Commands, SORTING for addi‐
    	      tional information regarding your selection of a sort field.
    
    
    	   ·  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	vztop  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 alternate-display mode.  How‐
           ever, some of these interactive commands are not available when running in Secure mode.
    
           If you wish to know in advance whether or not your vztop has been secured, simply ask for help and view the  sys‐
           tem summary on the second line.
    
    
    	 <Enter> or <Space>  :Refresh-Display
    	      These commands awaken vztop 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  com‐
    	      mands.  If vztop 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 filter‐
    	      ing and Other filtering.	See the `-p' command-line option for a discussion of PID monitoring, the `U'  or
    	      `u' interactive 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-DIS‐
    	      PLAY 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 primarily for use with dumb terminals, it can be
    	      applied anytime.
    
    	      Note: When this toggle is On and vztop 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) continu‐
    	      ous  updates,  with  an  unsatisfactory  display	as the system and tty driver try to keep up with vztop'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  vztop	 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 vztop 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 usually 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 win‐
    	      dows.  Otherwise, vztop 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 vztop 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)
    		  3) at any prompt, type <Esc>
    
    
    	  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 vztop program itself.
    
    	      A positive nice value will cause a process to lose priority.  Conversely, a negative 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
    		  3) at any prompt, type <Esc>
    
    
    	  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 vztop, 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 truncation 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
    						      nsUSER   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, vztop 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
    	      vztop.  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 vztop iterative display is paused.
    
    	      Note: This interactive command is only fully realized when supporting entries have been manually added  to
    	      the  end	of  the	 vztop	configuration file.  For details on creating 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 command 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 determine the position of messages and prompts.
    
           These  commands	always	impact just the `current' window/field group.  See topic 5. ALTERNATE-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 operating in full-screen mode
    	      or the `current' window name when operating in alternate-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' com‐
    	      mand toggles and whether or not vztop 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.
    
    	      This command serves as a 4-way toggle, cycling through these modes:
    		  1. detailed percentages by category (default)
    		  2. abbreviated user/system and total % + bar graph
    		  3. abbreviated user/system and total % + block graph
    		  4. turn off task and cpu states display
    
    	      When operating in either of the graphic modes, the display becomes much more  meaningful	when  individual
    	      CPUs  or NUMA nodes are also displayed.  See the the `1', `2' and `3' commands below for additional infor‐
    	      mation.
    
    
    	  m  :Memory/Swap-Usage toggle
    	      This command affects the two summary area lines dealing with physical and virtual memory.
    
    	      This command serves as a 4-way toggle, cycling through these modes:
    		  1. detailed percentages by memory type (default)
    		  2. abbreviated % used/total available + bar graph
    		  3. abbreviated % used/total available + block graph
    		  4. turn off memory display
    
    
    	  1  :Single/Separate-Cpu-States toggle
    	      This command affects how the `t' command's Cpu States portion is shown.  Although this toggle exists  pri‐
    	      marily 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 separately 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 summary display plus the cpu
    	      usage statistics for each NUMA Node.  It is only available 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  sta‐
    	      tistics  for  each  cpu  in that node will be shown until either the `1' or `2' command toggle is pressed.
    	      This interactive command is only available 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 Provisions).
    
    
           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.  It may also impact the summary area
    	      when a bar graph has been selected for cpu states or memory usage via the 't' or 'm' toggles.
    
    
    	  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 visible.  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 displayed, 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
    	      vztop 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 compilers, 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 vztop  to	display	 only  processes
    	      with users not matching the one provided.
    
    	      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 possible to toggle between program name and
    	      command line (see the `c' interactive command) 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 vztop supports most of the former vztop sort keys.  Since this is primarily a service
    	  to former vztop 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, vztop suggests that you temporarily turn  on  column  high‐
    	  lighting  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
    		 vztop 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 vztop dis‐
           play.
    
    
           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 vztop 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 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 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 com‐
    	  mands 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  visi‐
    	      ble  task	 display(s)  and  any task display(s) you had toggled 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 Win‐
    	      dow 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 previously applied, except for the  `i'  (idle	 tasks),
    	      `n' (max tasks), `u/U' (user filter), `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 chosen 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 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 displayed 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 remaining 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 positioned as the last displayed
    	   field.   Once  that field is reached via the right arrow key, and is thus the only column shown, you can con‐
    	   tinue 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 display 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 column 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 available 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, numbers, 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, vztop will attempt to locate the next occurrence.
    
    
           When  a	match  is found, the current window is repositioned vertically so the task row containing that string is
           first.  The scroll coordinates message can provide confirmation of  such	 vertical  repositioning  (see	the  `C'
           interactive command).  Horizontal scrolling, however, 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 produce a successful `&' search.
    
           The above interactive commands are always available in full-screen mode but never available in  alternate-display
           mode if the `current' window's task display has been toggled Off.
    
           Note:  Whenever	a Search is active in a window, vztop 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 this 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  vztop'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
    
    	  1. field names are case sensitive and spelled as in the header
    
    	  2. selection values need not comprise the full displayed field
    
    	  3. a selection is either case insensitive or sensitive to case
    
    	  4. the default is inclusion, prepending `!' denotes exclusions
    
    	  5. multiple selection criteria can be applied to a task window
    
    	  6. inclusion and exclusion criteria can be used simultaneously
    
    	  7. the 1 equality and 2 relational filters can be freely mixed
    
    	  8. 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 dis‐
    	  play.	 Later, should a filtered field become visible, the selection criteria 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 alternate-display mode.  As with the
    	     `=' interactive command, it too has additional consequences 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	require‐
    	  ments.   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 homogeneous.
    
    	  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 misleading 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, depending on the current  mem‐
    	  ory 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 displayed 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  reality,  each  filter  would
    	  have required separate input.	 The PR example shows the two concurrent 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:  Whenever	Other  Filtering is active in a window, vztop will turn 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 additional 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 vztop 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 vztop.  Rather, you create this file manually and place it in the
           /etc directory.	Its name must be `vztoprc' and must have no leading `.' (period).  It must have only two lines.
    
           Here is an example of the contents of /etc/vztoprc:
    	   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-vztop' + `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,graph modes
    	     "	    # line  c: summclr,msgsclr,headclr,taskclr
    	   global   # line 15: additional miscellaneous settings
    	     "	    # any remaining lines are devoted to the
    	     "	    # generalized inspect provisions
    	     "	    # discussed below
    
           If  the	$HOME  variable	 is  not present, vztop 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 vztop personal configuration file.
           Such  entries simply reflect a file to be read or command/pipeline to be executed whose results will then be dis‐
           played in a separate scrollable, searchable window.
    
           If you don't know the location or name of your vztop 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 `.vztoprc'.	 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" >> ~/.vztoprc
    	 "file\tNUMA Info\t/proc/%d/numa_maps" >> ~/.vztoprc
    	 "pipe\tLog\ttail -n200 /var/log/syslog | sort -Mr" >> ~/.vztoprc
    
           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 pre‐
           vent 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 vztop 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 selections 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 vztop a scheduling boost.  So plan on starting him with a nice value
           of -10, assuming you've got the authority.
    
    
       7a. Kernel Magic
           For these stupid tricks, vztop 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 schedul‐
    	  ing best, try a delay of .09 seconds or less.
    
    	  For this experiment, under x-windows open an xterm and maximize it.  Then do the following:
    	    . provide a scheduling boost and tiny delay via:
    		nice -n -10 vztop -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.
    
    
           ·  Under	 an xterm using `white-on-black' colors, on vztop'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  cur‐
    	  rently running tasks.
    
    
           ·  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 vztop, a 300% speed advantage.	As vztop
    	  climbs the TIME ladder, be as patient as you can while speculating on whether or not vztop will ever reach the
    	  vztop.
    
    
       7b. Bouncing Windows
           For these stupid tricks, vztop needs alternate-display mode.
    
    
           ·  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', sometimes several  task  displays  are  bouncing  and
    	  sometimes it's like an accordion, as vztop tries his best to allocate space.
    
    
           ·  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  win‐
    	  dows	--  hopping windows.
    
    
           ·  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.
    
    
           ·  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 displays 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 vztop 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.
    
    
           ·  Start vztop 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 vztop
           The original vztop was written by Roger Binns, based on Branko Lankester's <[email protected]> ps program.
    
           Robert Nation <[email protected]> adapted it for the proc file system.
    
           Helmut Geyer <[email protected]> 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, <[email protected]>
    
           With invaluable help from:
    	   Craig Small, <[email protected]>
    	   Albert Cahalan, <[email protected]>
    
    
    
    11. SEE Also
           free(1), ps(1), uptime(1), atop(1), slabtop(1), vmstat(8), w(1).
    
    
    
    vzprocps						July 2014						VZTOP(1)
    

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