Provided by: pcp_4.3.1-1_amd64 bug

NAME

       pcp-atop - Advanced System and Process Monitor

SYNOPSIS

       Interactive Usage:

       pcp  [pcp options] atop [-g|-m|-d|-n|-u|-p|-s|-c|-v|-o|-y] [-C|-M|-D|-N|-A] [-afFG1xR] [-L
       linelen] [-Plabel[,label]...] [interval [samples]]

       Writing and reading raw logfiles:

       pcp atop -w rawfile [-a] [-S] [interval [samples]]
       pcp atop -r [ rawfile  ]  [-b  hh:mm  ]  [-e  hh:mm  ]  [-g|-m|-d|-n|-u|-p|-s|-c|-v|-o|-y]
       [-C|-M|-D|-N|-A] [-fFG1xR] [-L linelen] [-Plabel[,label]...]

DESCRIPTION

       The  program  pcp-atop  is  an  interactive  monitor  to view various aspects of load on a
       system.  It shows  the  occupation  of  the  most  critical  hardware  resources  (from  a
       performance point of view) on system level, i.e. cpu, memory, disk and network.
       It  also  shows which processes are responsible for the indicated load with respect to cpu
       and memory load on process level.  Disk load is shown per process if "storage  accounting"
       is active in the kernel.

       Every interval (default: 10 seconds) information is shown about the resource occupation on
       system level (cpu, memory, disks and network layers), followed  by  a  list  of  processes
       which  have  been  active  during  the  last  interval  (note that all processes that were
       unchanged during the last interval are not shown, unless the key 'a' has been  pressed  or
       unless  sorting  on  memory occupation is done).  If the list of active processes does not
       entirely fit on the screen, only the top  of  the  list  is  shown  (sorted  in  order  of
       activity).
       The  intervals  are repeated till the number of samples (specified as command argument) is
       reached, or till the key 'q' is pressed in interactive mode.

       When invoked via the pcp(1) command,  the  PCPIntro(1)  options  -h/--host,  -a/--archive,
       -O/--origin,  -s/--samples,  -t/--interval,  -Z/--timezone  and  several other pcp options
       become indirectly available.  The  long  option  form  of  these  is  directly  available.
       Additionally,  the  --hotproc option can be used to request the per-process PCP metrics be
       used instead of the default proc metrics from pmdaproc(1).

       When pcp-atop is started, it checks whether the standard output channel is connected to  a
       screen,  or  to  a  file/pipe. In the first case it produces screen control codes (via the
       ncurses library) and behaves interactively; in the second case  it  produces  flat  ASCII-
       output.

       In  interactive  mode, the output of pcp-atop scales dynamically to the current dimensions
       of the screen/window.
       If the window is resized horizontally, columns will be added or removed automatically. For
       this  purpose,  every column has a particular weight. The columns with the highest weights
       that fit within the current width will be shown.
       If the window is resized vertically, lines of the process/thread list  will  be  added  or
       removed automatically.

       Furthermore  in  interactive  mode  the  output  of pcp-atop can be controlled by pressing
       particular keys.  However it is also possible to specify such key as flag on  the  command
       line. In that case pcp-atop switches to the indicated mode on beforehand; this mode can be
       modified again interactively. Specifying such  key  as  flag  is  especially  useful  when
       running  pcp-atop  with output to a pipe or file (non-interactively).  These flags are the
       same as the keys that  can  be  pressed  in  interactive  mode  (see  section  INTERACTIVE
       COMMANDS).
       Additional  flags  are available to support storage of pcp-atop data in PCP archive format
       (see section PCP DATA STORAGE).

COLORS

       For the resource consumption on system level, pcp-atop uses  colors  to  indicate  that  a
       critical   occupation  percentage  has  been  (almost)  reached.   A  critical  occupation
       percentage means that is likely that this load causes a  noticeable  negative  performance
       influence  for  applications  using  this resource. The critical percentage depends on the
       type of resource: e.g. the performance influence of a disk with a busy percentage  of  80%
       might be more noticeable for applications/user than a CPU with a busy percentage of 90%.
       Currently  pcp-atop  uses  the following default values to calculate a weighted percentage
       per resource:

        Processor
            A busy percentage of 90% or higher is considered `critical'.

        Disk
            A busy percentage of 70% or higher is considered `critical'.

        Network
            A busy percentage of 90% or higher  for  the  load  of  an  interface  is  considered
            `critical'.

        Memory
            An  occupation  percentage  of  90%  is  considered  `critical'.   Notice  that  this
            occupation percentage is the accumulated memory consumption of the kernel  (including
            slab)  and  all  processes;  the memory for the page cache (`cache' and `buff' in the
            MEM-line) and the reclaimable part of the slab (`slrec`) is not implied!
            If the number of pages swapped out (`swout' in the PAG-line) is larger  than  10  per
            second,  the  memory  resource  is  considered `critical'.  A value of at least 1 per
            second is considered `almost critical'.
            If the committed virtual memory exceeds the limit (`vmcom' and `vmlim'  in  the  SWP-
            line), the SWP-line is colored due to overcommitting the system.

        Swap
            An  occupation percentage of 80% is considered `critical' because swap space might be
            completely exhausted in the near future; it is not critical from a performance point-
            of-view.

       These  default  values can be modified in the configuration file (see separate man-page of
       pcp-atoprc).

       When a resource exceeds its critical occupation percentage, the concerning values  in  the
       screen line are colored red by default.
       When  a  resource  exceeded  (default)  80%  of  its  critical percentage (so it is almost
       critical), the concerning values in the screen line are  colored  cyan  by  default.  This
       `almost  critical  percentage'  (one  value  for  all  resources)  can  be modified in the
       configuration file (see separate man-page of pcp-atoprc).
       The default colors red and cyan can be modified in the configuration  file  as  well  (see
       separate man-page of pcp-atoprc).

       With the key 'x' (or flag -x), the use of colors can be suppressed.

GPU STATISTICS GATHERING

       GPU statistics can be gathered by pmdanvidia(1) which is a separate data collection daemon
       process.  It gathers cumulative utilization counters of every Nvidia GPU in the system, as
       well as utilization counters of every process that uses a GPU.  When atop notices that the
       daemon is active, it reads these GPU utilization counters with every interval.

       Find a description about the utilization counters in the section OUTPUT DESCRIPTION.

INTERACTIVE COMMANDS

       When running pcp-atop interactively (no  output  redirection),  keys  can  be  pressed  to
       control  the output. In general, lower case keys can be used to show other information for
       the active processes and upper case keys can be used to influence the sort  order  of  the
       active process/thread list.

       g    Show generic output (default).

            Per process the following fields are shown in case of a window-width of 80 positions:
            process-id, cpu consumption during the last interval in system  and  user  mode,  the
            virtual and resident memory growth of the process.

            The subsequent columns depend on the used kernel:
            When  the  kernel  supports  "storage  accounting" (>= 2.6.20), the data transfer for
            read/write on disk, the status and exit code are shown for each  process.   When  the
            kernel  does not support "storage accounting", the username, number of threads in the
            thread group, the status and exit code are shown.
            The last columns contain the state, the occupation percentage for the chosen resource
            (default: cpu) and the process name.

            When more than 80 positions are available, other information is added.

       m    Show memory related output.

            Per process the following fields are shown in case of a window-width of 80 positions:
            process-id, minor and major memory faults, size of virtual shared text, total virtual
            process  size,  total  resident process size, virtual and resident growth during last
            interval, memory occupation percentage and process name.

            When more than 80 positions are available, other information is added.

            For memory consumption, always all processes are shown (also the processes that  were
            not active during the interval).

       d    Show disk-related output.

            When  "storage  accounting"  is active in the kernel, the following fields are shown:
            process-id, amount of data read from disk, amount of data written to disk, amount  of
            data  that  was  written  but  has  been  withdrawn  again  (WCANCL), disk occupation
            percentage and process name.

       s    Show scheduling characteristics.

            Per process the following fields are shown in case of a window-width of 80 positions:
            process-id,  number  of  threads  in  state 'running' (R), number of threads in state
            'interruptible sleeping' (S), number of threads in state  'uninterruptible  sleeping'
            (D),  scheduling  policy  (normal  timesharing, realtime round-robin, realtime fifo),
            nice value, priority, realtime priority, current processor, status, exit code, state,
            the occupation percentage for the chosen resource and the process name.

            When more than 80 positions are available, other information is added.

       v    Show various process characteristics.

            Per process the following fields are shown in case of a window-width of 80 positions:
            process-id, user name and group, start date and time, status (e.g. exit code  if  the
            process  has  finished), state, the occupation percentage for the chosen resource and
            the process name.

            When more than 80 positions are available, other information is added.

       c    Show the command line of the process.

            Per process the following fields are shown: process-id, the occupation percentage for
            the chosen resource and the command line including arguments.

       e    Show GPU utilization.

            Per process at least the following fields are shown: process-id, range of GPU numbers
            on which the process currently runs, GPU busy percentage on  all  GPUs,  memory  busy
            percentage (i.e. read and write accesses on memory) on all GPUs, memory occupation at
            the moment of the sample, average  memory  occupation  during  the  sample,  and  GPU
            percentage.

            When the pmdanvidia daemon does not run with root privileges, the GPU busy percentage
            and the memory busy percentage are not available on process level.  In that case, the
            GPU percentage on process level reflects the GPU memory occupation instead of the GPU
            busy percentage (which is preferred).

       o    Show the user-defined line of the process.

            In the  configuration  file  the  keyword  ownprocline  can  be  specified  with  the
            description of a user-defined output-line.
            Refer to the man-page of pcp-atoprc for a detailed description.

       y    Show the individual threads within a process (toggle).

            Single-threaded processes are still shown as one line.
            For  multi-threaded processes, one line represents the process while additional lines
            show the activity per individual thread (in a  different  color).  Depending  on  the
            option  'a'  (all  or  active toggle), all threads are shown or only the threads that
            were active during the last interval.
            Whether this key is active or not can be seen in the header line.

       u    Show the process activity accumulated per user.

            Per user the following fields are shown: number of  processes  active  or  terminated
            during  last  interval  (or  in  total if combined with command `a'), accumulated cpu
            consumption during last interval in system and user mode,  the  current  virtual  and
            resident  memory  space consumed by active processes (or all processes of the user if
            combined with command `a').
            When "storage accounting" is active in the kernel, the  accumulated  read  and  write
            throughput  on  disk  is shown.  When the kernel module `netatop' has been installed,
            the number of received and sent network packets are shown.
            The last columns  contain  the  accumulated  occupation  percentage  for  the  chosen
            resource (default: cpu) and the user name.

       p    Show the process activity accumulated per program (i.e. process name).

            Per  program the following fields are shown: number of processes active or terminated
            during last interval (or in total if combined  with  command  `a'),  accumulated  cpu
            consumption  during  last  interval  in system and user mode, the current virtual and
            resident memory space consumed by active processes (or all processes of the  user  if
            combined with command `a').
            When  "storage  accounting"  is  active in the kernel, the accumulated read and write
            throughput on disk is shown.  When the kernel module `netatop'  has  been  installed,
            the number of received and sent network packets are shown.
            The  last  columns  contain  the  accumulated  occupation  percentage  for the chosen
            resource (default: cpu) and the program name.

       j    Show the process activity accumulated per Docker container.

            Per container  the  following  fields  are  shown:  number  of  processes  active  or
            terminated  during  last  interval  (or  in  total  if  combined  with  command `a'),
            accumulated cpu consumption during last interval in system and user mode, the current
            virtual  and  resident memory space consumed by active processes (or all processes of
            the user if combined with command `a').
            When "storage accounting" is active in the kernel, the  accumulated  read  and  write
            throughput  on  disk  is shown.  When the kernel module `netatop' has been installed,
            the number of received and sent network packets are shown.
            The last columns  contain  the  accumulated  occupation  percentage  for  the  chosen
            resource (default: cpu) and the Docker container id (CID).

       C    Sort  the  current  list in the order of cpu consumption (default).  The one-but-last
            column changes to ``CPU''.

       E    Sort the current list in the order of GPU utilization (preferred, but only applicable
            when  the  pmdanvidia  daemon  runs under root privileges) or the order of GPU memory
            occupation).  The one-but-last column changes to ``GPU''.

       M    Sort the current list in the order of resident memory consumption.  The  one-but-last
            column  changes  to ``MEM''. In case of sorting on memory, the full process list will
            be shown (not only the active processes).

       D    Sort the current list in the order of disk accesses issued.  The one-but-last  column
            changes to ``DSK''.

       N    Sort  the  current list in the order of network bandwidth (received and transmitted).
            The one-but-last column changes to ``NET''.

       A    Sort the current list automatically in the order of the  most  busy  system  resource
            during  this  interval.   The  one-but-last  column  shows either ``ACPU'', ``AMEM'',
            ``ADSK'' or ``ANET'' (the preceding 'A' indicates automatic sorting-order).  The most
            busy  resource is determined by comparing the weighted busy-percentages of the system
            resources, as described earlier in the section COLORS.
            This option remains valid until another sorting-order is explicitly selected again.
            A sorting-order for disk is only possible when "storage  accounting"  is  active.   A
            sorting-order  for  network  is  only  possible  when  the kernel module `netatop' is
            loaded.

       Miscellaneous interactive commands:

       ?    Request for help information (also the key 'h' can be pressed).

       V    Request for version information (version number and date).

       R    Gather and calculate the proportional set size of processes (toggle).   Gathering  of
            all  values that are needed to calculate the PSIZE of a process is a relatively time-
            consuming task, so this key should only be active when analyzing the resident  memory
            consumption of processes.

       x    Suppress colors to highlight critical resources (toggle).
            Whether this key is active or not can be seen in the header line.

       z    The pause key can be used to freeze the current situation in order to investigate the
            output on the screen. While pcp-atop is paused,  the  keys  described  above  can  be
            pressed  to show other information about the current list of processes.  Whenever the
            pause key is pressed again, pcp-atop will continue with a next sample.

       i    Modify the interval timer (default: 10  seconds).  If  an  interval  timer  of  0  is
            entered,  the  interval  timer is switched off. In that case a new sample can only be
            triggered manually by pressing the key 't'.

       t    Trigger a new sample manually. This key can be pressed if the current  sample  should
            be  finished  before  the  timer has exceeded, or if no timer is set at all (interval
            timer defined as 0). In the latter case pcp-atop  can  be  used  as  a  stopwatch  to
            measure  the  load  being  caused  by  a  particular application transaction, without
            knowing on beforehand how many seconds this transaction will last.

            When viewing the contents of a raw file, this key can be used to show the next sample
            from the file.

       T    When  viewing  the  contents of a raw file, this key can be used to show the previous
            sample from the file.

       b    When viewing the contents of a raw file, this key can be used to branch to a  certain
            timestamp within the file (either forward or backward).

       r    Reset all counters to zero to see the system and process activity since boot again.

            When  viewing  the  contents  of  a  raw  file, this key can be used to rewind to the
            beginning of the file again.

       U    Specify a search string for specific user names as a regular  expression.   From  now
            on,  only  (active)  processes  will  be  shown from a user which matches the regular
            expression.  The system statistics are  still  system  wide.   If  the  Enter-key  is
            pressed  without  specifying  a  name,  (active) processes of all users will be shown
            again.
            Whether this key is active or not can be seen in the header line.

       I    Specify a list with one or more PIDs to be selected.  From  now  on,  only  processes
            will  be shown with a PID which matches one of the given list.  The system statistics
            are still system wide.  If the Enter-key is pressed without  specifying  a  PID,  all
            (active) processes will be shown again.
            Whether this key is active or not can be seen in the header line.

       P    Specify a search string for specific process names as a regular expression.  From now
            on, only processes will be shown with a name which matches  the  regular  expression.
            The  system  statistics  are  still system wide.  If the Enter-key is pressed without
            specifying a name, all (active) processes will be shown again.
            Whether this key is active or not can be seen in the header line.

       /    Specify a specific command line search string as a regular expression.  From now  on,
            only  processes  will  be  shown  with  a  command  line  which  matches  the regular
            expression.  The system statistics are  still  system  wide.   If  the  Enter-key  is
            pressed without specifying a string, all (active) processes will be shown again.
            Whether this key is active or not can be seen in the header line.

       J    Specify  a  Docker  container  id  of 12 (hexadecimal) characters.  From now on, only
            processes will be shown that run in that specific Docker container (CID).  The system
            statistics  are  still system wide.  If the Enter-key is pressed without specifying a
            container id, all (active) processes will be shown again.
            Whether this key is active or not can be seen in the header line.

       S    Specify search strings for specific logical volume names,  specific  disk  names  and
            specific  network  interface  names.  All search strings are interpreted as a regular
            expressions.  From now on, only those system  resources  are  shown  that  match  the
            concerning  regular  expression.   If  the  Enter-key is pressed without specifying a
            search string, all (active) system resources of that type will be shown again.
            Whether this key is active or not can be seen in the header line.

       a    The `all/active' key can be used to  toggle  between  only  showing/accumulating  the
            processes that were active during the last interval (default) or showing/accumulating
            all processes.
            Whether this key is active or not can be seen in the header line.

       G    By default, pcp-atop shows/accumulates the processes that are alive and the processes
            that   are   exited   during   the   last   interval.   With   this   key   (toggle),
            showing/accumulating the processes that are exited can be suppressed.
            Whether this key is active or not can be seen in the header line.

       f    Show a fixed (maximum) number of header lines  for  system  resources  (toggle).   By
            default  only  the  lines  are  shown  about  system resources (CPUs, paging, logical
            volumes, disks, network interfaces) that really have  been  active  during  the  last
            interval.   With  this key you can force pcp-atop to show lines of inactive resources
            as well.
            Whether this key is active or not can be seen in the header line.

       F    Suppress sorting of system resources (toggle).  By default  system  resources  (CPUs,
            logical volumes, disks, network interfaces) are sorted on utilization.
            Whether this key is active or not can be seen in the header line.

       1    Show  relevant  counters as an average per second (in the format `..../s') instead of
            as a total during the interval (toggle).
            Whether this key is active or not can be seen in the header line.

       l    Limit the number of system level lines for the counters per-cpu, the active disks and
            the  network  interfaces.   By default lines are shown of all CPUs, disks and network
            interfaces which have been active during the last interval.  Limiting these lines can
            be  useful  on systems with huge number CPUs, disks or interfaces in order to be able
            to run pcp-atop on a screen/window with e.g. only 24 lines.
            For  all  mentioned  resources  the  maximum  number  of  lines  can   be   specified
            interactively.  When  using the flag -l the maximum number of per-cpu lines is set to
            0, the maximum number of disk lines to 5 and the maximum number of interface lines to
            3.  These values can be modified again in interactive mode.

       k    Send a signal to an active process (a.k.a. kill a process).

       q    Quit the program.

       PgDn Show the next page of the process/thread list.
            With the arrow-down key the list can be scrolled downwards with single lines.

       ^F   Show the next page of the process/thread list (forward).
            With the arrow-down key the list can be scrolled downwards with single lines.

       PgUp Show the previous page of the process/thread list.
            With the arrow-up key the list can be scrolled upwards with single lines.

       ^B   Show the previous page of the process/thread list (backward).
            With the arrow-up key the list can be scrolled upwards with single lines.

       ^L   Redraw the screen.

PCP DATA STORAGE

       In  order  to  store  system  and process level statistics for long-term analysis (e.g. to
       check the system load and the active processes running yesterday  between  3:00  and  4:00
       PM), pcp-atop can store the system and process level statistics in the PCP archive format,
       as an archive folio (see mkaf(1)).
       All information about processes and threads is stored in the archive.
       The interval (default: 10 seconds) and number of samples (default: infinite) can be passed
       as  last  arguments. Instead of the number of samples, the flag -S can be used to indicate
       that pcp-atop should finish anyhow before midnight.

       A PCP archive can be read and visualized again with the flag  -r  .   The  argument  is  a
       comma-separated  list  of  names,  each of which may be the base name of an archive or the
       name of a directory containing one or more archives.  If no  argument  is  specified,  the
       file  $PCP_LOG_DIR/pmlogger/HOST/YYYYMMDD  is  opened for input (where YYYYMMDD are digits
       representing the current date, and HOST is the hostname of the machine being logged).   If
       a  filename  is  specified  in the format YYYYMMDD (representing any valid date), the file
       $PCP_LOG_DIR/pmlogger/HOST/YYYYMMDD is opened.  If a filename with the symbolic name y  is
       specified,  yesterday's  daily logfile is opened (this can be repeated so 'yyyy' indicates
       the logfile of four days ago).
       The samples from the file can be viewed interactively by using the key  't'  to  show  the
       next  sample,  the  key  'T'  to  show  the  previous  sample,  the key 'b' to branch to a
       particular time or the key 'r' to rewind to the begin of the file.
       When output is redirected to a file or pipe, pcp-atop prints all samples in  plain  ASCII.
       The  default  line  length  is 80 characters in that case; with the flag -L followed by an
       alternate line length, more (or less) columns will be shown.
       With the flag -b (begin time) and/or -e (end time) followed by a time argument of the form
       HH:MM, a certain time period within the raw file can be selected.

OUTPUT DESCRIPTION

       The  first  sample  shows  the  system  level activity since boot (the elapsed time in the
       header shows the time since boot).  Note that particular counters could have reached their
       maximum value (several times) and started by zero again, so do not rely on these figures.

       For  every  sample  pcp-atop  first shows the lines related to system level activity. If a
       particular system resource has not been used during the interval, the entire line  related
       to  this  resource  is  suppressed.  So the number of system level lines may vary for each
       sample.
       After that a list is shown of processes which have been active during the  last  interval.
       This  list  is  by default sorted on cpu consumption, but this order can be changed by the
       keys which are previously described.

       If values have to be shown by pcp-atop which do not  fit  in  the  column  width,  another
       format  is  used.  If  e.g.  a cpu-consumption of 233216 milliseconds should be shown in a
       column width of 4 positions, it is  shown  as  `233s'  (in  seconds).   For  large  memory
       figures, another unit is chosen if the value does not fit (Mb instead of Kb, Gb instead of
       Mb, Tb instead of Gb, ...).  For other values, a kind of exponent notation is used  (value
       123456789 shown in a column of 5 positions gives 123e6).

OUTPUT DESCRIPTION - SYSTEM LEVEL

       The system level information consists of the following output lines:

       PRC  Process and thread level totals.
            This  line  contains  the  total cpu time consumed in system mode (`sys') and in user
            mode (`user'), the total number of processes present at this  moment  (`#proc'),  the
            total  number  of  threads  present  at  this  moment  in  state `running' (`#trun'),
            `sleeping interruptible' (`#tslpi') and `sleeping  uninterruptible'  (`#tslpu'),  the
            number  of zombie processes (`#zombie'), the number of clone system calls (`clones'),
            and the number of processes that ended during the  interval  (`#exit')  when  process
            accounting  is  used.  Instead  of  `#exit` the last column may indicate that process
            accounting could not be activated (`no procacct`).
            If the screen-width does not allow all of these counters, only a relevant  subset  is
            shown.

       CPU  CPU utilization.
            At least one line is shown for the total occupation of all CPUs together.
            In case of a multi-processor system, an additional line is shown for every individual
            processor (with `cpu' in lower case), sorted on activity. Inactive CPUs will  not  be
            shown by default.  The lines showing the per-cpu occupation contain the cpu number in
            the field combined with the wait percentage.

            Every line contains the percentage of cpu time spent in kernel  mode  by  all  active
            processes  (`sys'), the percentage of cpu time consumed in user mode (`user') for all
            active processes (including processes running with a nice value  larger  than  zero),
            the  percentage  of  cpu time spent for interrupt handling (`irq') including softirq,
            the percentage of unused cpu time while  no  processes  were  waiting  for  disk  I/O
            (`idle'),  and  the  percentage  of  unused  cpu  time while at least one process was
            waiting for disk I/O (`wait').
            In case of per-cpu occupation, the cpu number and the wait percentage (`w') for  that
            cpu.  The number of lines showing the per-cpu occupation can be limited.

            For virtual machines, the steal-percentage (`steal') shows the percentage of cpu time
            stolen by other virtual machines running on the same hardware.
            For physical machines hosting one or  more  virtual  machines,  the  guest-percentage
            (`guest')  shows the percentage of cpu time used by the virtual machines. Notice that
            this percentage overlaps the user-percentage!

            When PMC performance monitoring counters are supported by the CPU and the kernel (and
            pcp-atop runs with root privileges), the number of instructions per CPU cycle (`ipc')
            is shown.  The first sample always shows the value 'initial',  because  the  counters
            are just activated at the moment that pcp-atop is started.
            When  the CPU busy percentage is high and the IPC is less than 1.0, it is likely that
            the CPU is frequently waiting for memory access during instruction execution  (larger
            CPU  caches  or faster memory might be helpful to improve performance).  When the CPU
            busy percentage is high and the IPC is greater than 1.0, it is likely that the CPU is
            instruction-bound (more/faster cores might be helpful to improve performance).
            Furthermore,  per  CPU  the effective number of cycles (`cycl') is shown.  This value
            can reach the current CPU frequency if such CPU is 100% busy.  When an  idle  CPU  is
            halted,  the  number of effective cycles can be (considerably) lower than the current
            frequency.
            Notice that the average instructions per cycle and number of cycles is shown  in  the
            CPU line for all CPUs.
            See also: http://www.brendangregg.com/blog/2017-05-09/cpu-utilization-is-wrong.html

            In  case  of frequency scaling, all previously mentioned CPU percentages are relative
            to the used scaling of the CPU during the interval.  If a CPU  has  been  active  for
            e.g. 50% in user mode during the interval while the frequency scaling of that CPU was
            40%, only 20% of the full capacity of the CPU has been used in user mode.

            If the screen-width does not allow all of these counters, only a relevant  subset  is
            shown.

       CPL  CPU load information.
            This line contains the load average figures reflecting the number of threads that are
            available to run on a CPU (i.e. part of the runqueue) or that are  waiting  for  disk
            I/O. These figures are averaged over 1 (`avg1'), 5 (`avg5') and 15 (`avg15') minutes.
            Furthermore the number of context switches (`csw'), the number of serviced interrupts
            (`intr') and the number of available CPUs are shown.

            If the screen-width does not allow all of these counters, only a relevant  subset  is
            shown.

       GPU  GPU utilization (Nvidia).
            Read  the section GPU STATISTICS GATHERING in this document to find the details about
            the activation of the pmdanvidia daemon.

            In the first column of every line, the bus-id (last  nine  characters)  and  the  GPU
            number  are  shown.   The  subsequent columns show the percentage of time that one or
            more kernels were executing on the GPU  (`gpubusy'),  the  percentage  of  time  that
            global  (device)  memory  was  being  read  or  written  (`membusy'),  the occupation
            percentage of memory (`memocc'), the total memory (`total'), the memory being in  use
            at  the  moment  of  the  sample (`used'), the average memory being in use during the
            sample time (`usavg'), the number of processes being active on the GPU at the  moment
            of the sample (`#proc'), and the type of GPU.

            If  the  screen-width does not allow all of these counters, only a relevant subset is
            shown.
            The number of lines showing the GPUs can be limited.

       MEM  Memory occupation.
            This line contains the total amount of physical memory (`tot'), the amount of  memory
            which is currently free (`free'), the amount of memory in use as page cache including
            the total resident shared memory (`cache'), the amount  of  memory  within  the  page
            cache  that  has  to  be  flushed  to  disk  (`dirty'), the amount of memory used for
            filesystem meta data (`buff'), the amount of memory being  used  for  kernel  mallocs
            (`slab'),  the amount of slab memory that is reclaimable (`slrec'), the resident size
            of shared memory including tmpfs  (`shmem`),  the  resident  size  of  shared  memory
            (`shrss`) the amount of shared memory that is currently swapped (`shswp`), the amount
            of memory that is currently claimed by vmware's balloon driver (`vmbal`), the  amount
            of  memory  that  is  claimed  for  huge pages (`hptot`), and the amount of huge page
            memory that is really in use (`hpuse`).

            If the screen-width does not allow all of these counters, only a relevant  subset  is
            shown.

       SWP  Swap occupation and overcommit info.
            This  line  contains the total amount of swap space on disk (`tot') and the amount of
            free swap space (`free').
            Furthermore the committed virtual memory space (`vmcom') and the maximum limit of the
            committed  space  (`vmlim', which is by default swap size plus 50% of memory size) is
            shown.  The committed space is the reserved virtual  space  for  all  allocations  of
            private  memory  space  for processes. The kernel only verifies whether the committed
            space   exceeds   the   limit   if   strict   overcommit   handling   is   configured
            (vm.overcommit_memory is 2).

       PAG  Paging frequency.
            This  line  contains  the  number of scanned pages (`scan') due to the fact that free
            memory drops below a particular threshold and the number times that the kernel  tries
            to reclaim pages due to an urgent need (`stall').
            Also  the  number  of  memory  pages the system read from swap space (`swin') and the
            number of memory pages the system wrote to swap space (`swout') are shown.

       PSI  Pressure Stall Information.
            This line contains three percentages per category: average pressure  percentage  over
            the last 10, 60 and 300 seconds (separated by slashes).
            The  categories  are:  CPU  for  'some'  (`cs'), memory for 'some' (`ms'), memory for
            'full' (`mf'), I/O for 'some' (`is'), and I/O for 'full' (`if').

       LVM/MDD/DSK
            Logical volume/multiple device/disk utilization.
            Per active unit one line is produced, sorted on unit activity.  Such line  shows  the
            name  (e.g.  VolGroup00-lvtmp  for a logical volume or sda for a hard disk), the busy
            percentage i.e. the portion  of  time  that  the  unit  was  busy  handling  requests
            (`busy'),  the  number of read requests issued (`read'), the number of write requests
            issued (`write'), the number of KiBytes per read (`KiB/r'), the number of KiBytes per
            write (`KiB/w'), the number of MiBytes per second throughput for reads (`MBr/s'), the
            number of MiBytes per second throughput for writes (`MBw/s'), the average queue depth
            (`avq') and the average number of milliseconds needed by a request (`avio') for seek,
            latency and data transfer.
            If the screen-width does not allow all of these counters, only a relevant  subset  is
            shown.

            The number of lines showing the units can be limited per class (LVM, MDD or DSK) with
            the 'l' key or statically (see separate man-page of  pcp-atoprc(5)).   By  specifying
            the value 0 for a particular class, no lines will be shown any more for that class.

       NFM  Network Filesystem (NFS) mount at the client side.
            For  each  NFS-mounted  filesystem,  a line is shown that contains the mounted server
            directory, the name of the server (`srv'), the total number of bytes physically  read
            from  the  server  (`read')  and  the total number of bytes physically written to the
            server (`write').  Data transfer is subdivided in the number of bytes read via normal
            read()  system  calls (`nread'), the number of bytes written via normal read() system
            calls (`nwrit'), the number of bytes read via direct I/O  (`dread'),  the  number  of
            bytes  written  via  direct I/O (`dwrit'), the number of bytes read via memory mapped
            I/O pages (`mread'), and the number of bytes written  via  memory  mapped  I/O  pages
            (`mwrit').

       NFC  Network Filesystem (NFS) client side counters.
            This  line  contains  the  number of RPC calls issues by local processes (`rpc'), the
            number of read RPC calls (`read`) and write RPC calls (`rpwrite') issued to  the  NFS
            server,  the  number  of  RPC calls being retransmitted (`retxmit') and the number of
            authorization refreshes (`autref').

       NFS  Network Filesystem (NFS) server side counters.
            This line contains the number of RPC calls received from  NFS  clients  (`rpc'),  the
            number  of  read RPC calls received (`cread`), the number of write RPC calls received
            (`cwrit'), the number of  Megabytes/second  returned  to  read  requests  by  clients
            (`MBcr/s`),  the  number  of  Megabytes/second  passed  in  write requests by clients
            (`MBcw/s`), the number of network requests handled via TCP (`nettcp'), the number  of
            network  requests  handled  via  UDP  (`netudp'),  the  number  of  reply  cache hits
            (`rchits'), the number of reply cache misses (`rcmiss') and the  number  of  uncached
            requests  (`rcnoca').   Furthermore  some  error  counters  indicating  the number of
            requests with a bad format (`badfmt')  or  a  bad  authorization  (`badaut'),  and  a
            counter indicating the number of bad clients (`badcln').

       NET  Network utilization (TCP/IP).
            One line is shown for activity of the transport layer (TCP and UDP), one line for the
            IP layer and one line per active interface.
            For the transport layer, counters are shown concerning the  number  of  received  TCP
            segments  including  those  received in error (`tcpi'), the number of transmitted TCP
            segments excluding those containing only retransmitted octets (`tcpo'), the number of
            UDP  datagrams  received  (`udpi'), the number of UDP datagrams transmitted (`udpo'),
            the number of active TCP opens (`tcpao'), the number of passive TCP opens  (`tcppo'),
            the  number  of  TCP output retransmissions (`tcprs'), the number of TCP input errors
            (`tcpie'), the number of TCP output resets (`tcpor'), the  number  of  UDP  no  ports
            (`udpnp'), and the number of UDP input errors (`udpie').
            If  the  screen-width does not allow all of these counters, only a relevant subset is
            shown.
            These counters are related to IPv4 and IPv6 combined.

            For the IP layer, counters are shown concerning the number of IP  datagrams  received
            from  interfaces,  including  those  received  in  error  (`ipi'),  the  number of IP
            datagrams that local higher-layer protocols offered  for  transmission  (`ipo'),  the
            number  of  received IP datagrams which were forwarded to other interfaces (`ipfrw'),
            the number of IP datagrams which  were  delivered  to  local  higher-layer  protocols
            (`deliv'),  the  number  of  received  ICMP  datagrams  (`icmpi'),  and the number of
            transmitted ICMP datagrams (`icmpo').
            If the screen-width does not allow all of these counters, only a relevant  subset  is
            shown.
            These counters are related to IPv4 and IPv6 combined.

            For  every  active  network  interface  one  line  is  shown, sorted on the interface
            activity.  Such line shows the name of the interface and its busy percentage  in  the
            first  column.   The  busy  percentage for half duplex is determined by comparing the
            interface speed with the number of bits transmitted and received per second; for full
            duplex  the interface speed is compared with the highest of either the transmitted or
            the received bits.  When the interface speed can not  be  determined  (e.g.  for  the
            loopback interface), `---' is shown instead of the percentage.
            Furthermore  the  number  of  received  packets  (`pcki'),  the number of transmitted
            packets (`pcko'), the line speed of the interface (`sp'),  the  effective  amount  of
            bits  received per second (`si'), the effective amount of bits transmitted per second
            (`so'), the number of collisions (`coll'), the number of received  multicast  packets
            (`mlti'),  the  number  of  errors  while  receiving a packet (`erri'), the number of
            errors while transmitting a packet (`erro'), the number of received  packets  dropped
            (`drpi'), and the number of transmitted packets dropped (`drpo').
            If  the  screen-width does not allow all of these counters, only a relevant subset is
            shown.
            The number of lines showing the network interfaces can be limited.

       IFB  Infiniband utilization.
            For every active Infiniband port one line is shown, sorted on  activity.   Such  line
            shows  the  name  of  the port and its busy percentage in the first column.  The busy
            percentage is determined by taking the highest  of  either  the  transmitted  or  the
            received  bits during the interval, multiplying that value by the number of lanes and
            comparing it against the maximum port speed.
            Furthermore the number of received packets divided by the number of  lanes  (`pcki'),
            the  number  of  transmitted  packets  divided  by  the number of lanes (`pcko'), the
            maximum line speed (`sp'), the effective amount of bits received per  second  (`si'),
            the  effective  amount of bits transmitted per second (`so'), and the number of lanes
            (`lanes').
            If the screen-width does not allow all of these counters, only a relevant  subset  is
            shown.
            The number of lines showing the Infiniband ports can be limited.

OUTPUT DESCRIPTION - PROCESS LEVEL

       Following  the  system  level information, the processes are shown from which the resource
       utilization has changed during the last interval. These processes might have used cpu time
       or issued disk or network requests. However a process is also shown if part of it has been
       paged out due to lack of memory (while the process itself was in sleep state).

       Per process the following fields may be shown (in alphabetical order),  depending  on  the
       current  output mode as described in the section INTERACTIVE COMMANDS and depending on the
       current width of your window:

       AVGRSZ   The average size of one read-action on disk.

       AVGWSZ   The average size of one write-action on disk.

       CID      Container ID (Docker) of 12 hexadecimal digits, referring  to  the  container  in
                which  the process/thread is running.  If a process has been started and finished
                during the last interval, a `?' is shown because the container ID is not part  of
                the standard process accounting record.

       CMD      The  name  of  the  process.   This name can be surrounded by "less/greater than"
                signs (`<name>') which means that  the  process  has  finished  during  the  last
                interval.
                Behind the abbreviation `CMD' in the header line, the current page number and the
                total number of pages of the process/thread list are shown.

       COMMAND-LINE
                The full command line of the process (including arguments). If the length of  the
                command  line exceeds the length of the screen line, the arrow keys -> and <- can
                be used for horizontal scroll.
                Behind the verb `COMMAND-LINE' in the header line, the current  page  number  and
                the total number of pages of the process/thread list are shown.

       CPU      The  occupation  percentage of this process related to the available capacity for
                this resource on system level.

       CPUNR    The identification of the CPU the (main) thread is running  on  or  has  recently
                been running on.

       CTID     Container  ID  (OpenVZ).   If  a process has been started and finished during the
                last interval, a `?' is shown because  the  container  ID  is  not  part  of  the
                standard process accounting record.

       DSK      The  occupation  percentage  of  this  process  related to the total load that is
                produced by all processes (i.e. total disk accesses by all processes  during  the
                last interval).
                This  information is shown when per process "storage accounting" is active in the
                kernel.

       EGID     Effective group-id under which this process executes.

       ENDATE   Date that the process has been finished. If the process is  still  running,  this
                field shows `active'.

       ENTIME   Time  that  the  process has been finished. If the process is still running, this
                field shows `active'.

       ENVID    Virtual environment identified (OpenVZ only).

       EUID     Effective user-id under which this process executes.

       EXC      The exit code of a terminated process (second position of column `ST'  is  E)  or
                the fatal signal number (second position of column `ST' is S or C).

       FSGID    Filesystem group-id under which this process executes.

       FSUID    Filesystem user-id under which this process executes.

       GPU      When  the pmdanvidia daemon does not run with root privileges, the GPU percentage
                reflects the GPU memory occupation percentage (memory of all GPUs is 100%).
                When the pmdanvidia daemon runs with root privileges, the GPU percentage reflects
                the GPU busy percentage.

       GPUBUSY  Busy percentage on all GPUs (one GPU is 100%).
                When  the  pmdanvidia daemon does not run with root privileges, this value is not
                available.

       GPUNUMS  Comma-separated list of GPUs used by the process during the  interval.  When  the
                comma-separated  list  exceeds  the  width  of the column, a hexadecimal value is
                shown.

       MAJFLT   The number of page faults issued  by  this  process  that  have  been  solved  by
                creating/loading the requested memory page.

       MEM      The  occupation  percentage of this process related to the available capacity for
                this resource on system level.

       MEMAVG   Average memory occupation during the interval on all used GPUs.

       MEMBUSY  Busy percentage of memory on all GPUs (one GPU is 100%), i.e.   the  time  needed
                for read and write accesses on memory.
                When  the  pmdanvidia daemon does not run with root privileges, this value is not
                available.

       MEMNOW   Memory occupation at the moment of the sample on all used GPUs.

       MINFLT   The number of page faults issued  by  this  process  that  have  been  solved  by
                reclaiming the requested memory page from the free list of pages.

       NET      The  occupation  percentage  of  this  process  related to the total load that is
                produced by all processes (i.e.  consumed  network  bandwidth  of  all  processes
                during the last interval).
                This information will only be shown when kernel module `netatop' is loaded.

       NICE     The  more  or less static priority that can be given to a process on a scale from
                -20 (high priority) to +19 (low priority).

       NPROCS   The number of active and  terminated  processes  accumulated  for  this  user  or
                program.

       PID      Process-id.

       POLI     The  policies  'norm'  (normal,  which is SCHED_OTHER), 'btch' (batch) and 'idle'
                refer to timesharing processes.  The policies 'fifo' (SCHED_FIFO) and 'rr' (round
                robin, which is SCHED_RR) refer to realtime processes.

       PPID     Parent process-id.

       PRI      The  process' priority ranges from 0 (highest priority) to 139 (lowest priority).
                Priority 0 to 99 are used for realtime processes (fixed priority  independent  of
                their  behavior)  and  priority  100  to  139 for timesharing processes (variable
                priority depending on their recent CPU consumption and the nice value).

       PSIZE    The proportional memory size of this process (or user).
                Every process shares resident memory with other processes. E.g. when a particular
                program  is  started several times, the code pages (text) are only loaded once in
                memory and shared by all incarnations. Also  the  code  of  shared  libraries  is
                shared  by  all processes using that shared library, as well as shared memory and
                memory-mapped files.  For the PSIZE calculation of a process, the resident memory
                of  a  process  that  is  shared with other processes is divided by the number of
                sharers.  This means, that every process is accounted for a proportional part  of
                that memory. Accumulating the PSIZE values of all processes in the system gives a
                reliable impression of the total resident memory consumed by all processes.
                Since gathering of all values that  are  needed  to  calculate  the  PSIZE  is  a
                relatively  time-consuming  task,  the  'R'  key (or '-R' flag) should be active.
                Gathering these values also requires  superuser  privileges  (otherwise  '?K'  is
                shown in the output).

       RDDSK    When the kernel maintains standard io statistics (>= 2.6.20):
                The  read data transfer issued physically on disk (so reading from the disk cache
                is not accounted for).
                Unfortunately, the kernel aggregates the data tranfer of a process  to  the  data
                transfer  of  its parent process when terminating, so you might see transfers for
                (parent) processes like cron, bash or init, that are not really issued by them.

       RGID     The real group-id under which the process executes.

       RGROW    The amount of resident  memory  that  the  process  has  grown  during  the  last
                interval. A resident growth can be caused by touching memory pages which were not
                physically created/loaded before (load-on-demand).  Note that a  resident  growth
                can  also  be  negative e.g. when part of the process is paged out due to lack of
                memory or when the process frees dynamically allocated  memory.   For  a  process
                which  started  during  the last interval, the resident growth reflects the total
                resident size of the process at that moment.

       RSIZE    The total resident memory usage consumed by this process (or user).  Notice  that
                the RSIZE of a process includes all resident memory used by that process, even if
                certain memory parts are shared with other processes (see also the explanation of
                PSIZE).

       RTPR     Realtime priority according the POSIX standard.  Value can be 0 for a timesharing
                process (policy 'norm', 'btch' or 'idle') or  ranges  from  1  (lowest)  till  99
                (highest) for a realtime process (policy 'rr' or 'fifo').

       RUID     The real user-id under which the process executes.

       S        The  current state of the (main) thread: `R' for running (currently processing or
                in the runqueue), `S' for sleeping interruptible (wait for an  event  to  occur),
                `D'  for  sleeping  non-interruptible, `Z' for zombie (waiting to be synchronized
                with its parent  process),  `T'  for  stopped  (suspended  or  traced),  `W'  for
                swapping,  and  `E'  (exit)  for  processes  which  have finished during the last
                interval.

       SGID     The saved group-id of the process.

       ST       The status of a process.
                The first position indicates if the process has  been  started  during  the  last
                interval (the value N means 'new process').

                The  second  position  indicates if the process has been finished during the last
                interval.
                The value E means 'exit' on  the  process'  own  initiative;  the  exit  code  is
                displayed in the column `EXC'.
                The value S means that the process has been terminated unvoluntarily by a signal;
                the signal number is displayed in the in the column `EXC'.
                The value C means that the process has been terminated unvoluntarily by a signal,
                producing a core dump in its current directory; the signal number is displayed in
                the column `EXC'.

       STDATE   The start date of the process.

       STTIME   The start time of the process.

       SUID     The saved user-id of the process.

       SWAPSZ   The swap space consumed by this process (or user).

       SYSCPU   CPU time consumption of this process in system mode (kernel mode), usually due to
                system call handling.

       THR      Total  number  of threads within this process.  All related threads are contained
                in a thread group, represented by pcp-atop as one line or as a separate line when
                the 'y' key (or -y flag) is active.

                On  Linux  2.4  systems  it  is  hardly possible to determine which threads (i.e.
                processes) are related to the same thread group.  Every thread is represented  by
                pcp-atop as a separate line.

       TID      Thread-id.   All  threads  within  a  process  run  with  the same PID but with a
                different TID. This value is  shown  for  individual  threads  in  multi-threaded
                processes (when using the key 'y').

       TRUN     Number of threads within this process that are in the state 'running' (R).

       TSLPI    Number  of  threads  within  this  process  that  are in the state 'interruptible
                sleeping' (S).

       TSLPU    Number of threads within this process that  are  in  the  state  'uninterruptible
                sleeping' (D).

       USRCPU   CPU  time  consumption  of  this  process in user mode, due to processing the own
                program text.

       VDATA    The virtual memory size of the private data used by this process (including  heap
                and shared library data).

       VGROW    The amount of virtual memory that the process has grown during the last interval.
                A virtual growth can be caused by e.g. issueing a malloc() or attaching a  shared
                memory  segment. Note that a virtual growth can also be negative by e.g. issueing
                a free() or detaching a shared memory  segment.   For  a  process  which  started
                during  the  last interval, the virtual growth reflects the total virtual size of
                the process at that moment.

       VPID     Virtual process-id (within an OpenVZ container).  If a process has  been  started
                and  finished  during  the  last  interval,  a  `?'  is shown because the virtual
                process-id is not part of the standard process accounting record.

       VSIZE    The total virtual memory usage consumed by this process (or user).

       VSLIBS   The virtual memory size of the (shared) text of all shared libraries used by this
                process.

       VSTACK   The virtual memory size of the (private) stack used by this process

       VSTEXT   The virtual memory size of the (shared) text of the executable program.

       WRDSK    When the kernel maintains standard io statistics (>= 2.6.20):
                The  write  data transfer issued physically on disk (so writing to the disk cache
                is not accounted for).  This counter is maintained for  the  application  process
                that  writes  its  data  to  the  cache  (assuming  that  this data is physically
                transferred to disk later on). Notice that disk I/O needed for  swapping  is  not
                taken into account.
                Unfortunately,  the  kernel  aggregates the data tranfer of a process to the data
                transfer of its parent process when terminating, so you might see  transfers  for
                (parent) processes like cron, bash or init, that are not really issued by them.

       WCANCL   When the kernel maintains standard io statistics (>= 2.6.20):
                The  write data transfer previously accounted for this process or another process
                that has been cancelled.  Suppose that a process writes new data to  a  file  and
                that  data  is  removed again before the cache buffers have been flushed to disk.
                Then the original process shows the written data as WRDSK, while the process that
                removes/truncates the file shows the unflushed removed data as WCANCL.

PARSEABLE OUTPUT

       With  the  flag  -P  followed by a list of one or more labels (comma-separated), parseable
       output is produced for each sample.  The labels that can  be  specified  for  system-level
       statistics  correspond  to  the  labels (first verb of each line) that can be found in the
       interactive output: "CPU", "cpu", "CPL", "GPU", "MEM", "SWP", "PAG", "PSI", "LVM",  "MDD",
       "DSK", "NFM", "NFC", "NFS", "NET" and "IFB".
       For  process-level statistics special labels are introduced: "PRG" (general), "PRC" (cpu),
       "PRE" (GPU), "PRM" (memory), "PRD" (disk, only if "storage accounting" is active).
       With the label "ALL", all system and process level statistics are shown.

       For every interval all requested lines are shown whereafter pcp-atop  shows  a  line  just
       containing  the  label  "SEP"  as  a  separator  before  the lines for the next sample are
       generated.
       When a sample contains the values since boot, pcp-atop shows a line  just  containing  the
       label "RESET" before the lines for this sample are generated.

       The  first  part of each output-line consists of the following six fields: label (the name
       of the label), host (the name of this machine), epoch (the time of this interval as number
       of  seconds since 1-1-1970), date (date of this interval in format YYYY/MM/DD), time (time
       of this interval in format HH:MM:SS), and interval (number of  seconds  elapsed  for  this
       interval).

       The subsequent fields of each output-line depend on the label:

       CPU      Subsequent  fields:  total  number  of  clock-ticks  per second for this machine,
                number of processors, consumption for all  CPUs  in  system  mode  (clock-ticks),
                consumption  for all CPUs in user mode (clock-ticks), consumption for all CPUs in
                user mode for niced processes (clock-ticks), consumption for  all  CPUs  in  idle
                mode  (clock-ticks),  consumption  for  all  CPUs  in  wait  mode  (clock-ticks),
                consumption for all CPUs in irq mode (clock-ticks), consumption for all  CPUs  in
                softirq mode (clock-ticks), consumption for all CPUs in steal mode (clock-ticks),
                consumption for all CPUs in  guest  mode  (clock-ticks)  overlapping  user  mode,
                frequency of all CPUs and frequency percentage of all CPUs.

       cpu      Subsequent  fields:  total  number  of  clock-ticks  per second for this machine,
                processor-number,  consumption  for  this  CPU  in  system  mode   (clock-ticks),
                consumption  for this CPU in user mode (clock-ticks), consumption for this CPU in
                user mode for niced processes (clock-ticks), consumption for  this  CPU  in  idle
                mode  (clock-ticks),  consumption  for  this  CPU  in  wait  mode  (clock-ticks),
                consumption for this CPU in irq mode (clock-ticks), consumption for this  CPU  in
                softirq mode (clock-ticks), consumption for this CPU in steal mode (clock-ticks),
                consumption for this CPU in  guest  mode  (clock-ticks)  overlapping  user  mode,
                frequency of all CPUs, frequency percentage of all CPUs, instructions executed by
                all CPUs and cycles for all CPUs.

       CPL      Subsequent fields: number of processors,  load  average  for  last  minute,  load
                average  for  last five minutes, load average for last fifteen minutes, number of
                context-switches, and number of device interrupts.

       GPU      Subsequent fields: GPU number, bus-id  string,  type  of  GPU  string,  GPU  busy
                percentage  during  last  second  (-1  if  not available), memory busy percentage
                during last second (-1 if not available), total memory size  (KiB),  used  memory
                (KiB)  at  this  moment,  number of samples taken during interval, cumulative GPU
                busy percentage during the interval (to be divided by the number of  samples  for
                the  average  busy  percentage,  -1  if  not  available),  cumulative memory busy
                percentage during the interval (to be divided by the number of  samples  for  the
                average  busy  percentage, -1 if not available), and cumulative memory occupation
                during the interval (to be divided by the  number  of  samples  for  the  average
                occupation).

       MEM      Subsequent fields: page size for this machine (in bytes), size of physical memory
                (pages), size of free memory (pages), size of page cache (pages), size of  buffer
                cache  (pages),  size  of slab (pages), dirty pages in cache (pages), reclaimable
                part of slab (pages), total size of vmware's balloon pages (pages), total size of
                shared  memory  (pages),  size of resident shared memory (pages), size of swapped
                shared memory (pages), huge page size (in bytes), total size of huge pages  (huge
                pages), and size of free huge pages (huge pages).

       SWP      Subsequent  fields:  page size for this machine (in bytes), size of swap (pages),
                size of free swap (pages), 0 (future use), size of committed space  (pages),  and
                limit for committed space (pages).

       PAG      Subsequent  fields:  page size for this machine (in bytes), number of page scans,
                number of allocstalls, 0 (future use), number of swapins, and number of swapouts.

       PSI      Subsequent fields: PSI statistics present on this  system  (n  or  y),  CPU  some
                avg10,  CPU some avg60, CPU some avg300, CPU some accumulated microseconds during
                interval, memory some avg10, memory some avg60, memory some avg300,  memory  some
                accumulated  microseconds  during interval, memory full avg10, memory full avg60,
                memory full avg300, memory full accumulated  microseconds  during  interval,  I/O
                some  avg10,  I/O  some avg60, I/O some avg300, I/O some accumulated microseconds
                during interval, I/O full avg10, I/O full avg60, I/O full avg300,  and  I/O  full
                accumulated microseconds during interval.

       LVM/MDD/DSK
                For every logical volume/multiple device/hard disk one line is shown.
                Subsequent  fields:  name,  number of milliseconds spent for I/O, number of reads
                issued, number of sectors transferred for reads, number  of  writes  issued,  and
                number of sectors transferred for write.

       NFM      Subsequent  fields:  mounted  NFS  filesystem,  total number of bytes read, total
                number of bytes written, number of bytes read by normal system calls,  number  of
                bytes  written by normal system calls, number of bytes read by direct I/O, number
                of bytes written by direct I/O, number of pages read by  memory-mapped  I/O,  and
                number of pages written by memory-mapped I/O.

       NFC      Subsequent  fields:  number of transmitted RPCs, number of transmitted read RPCs,
                number of transmitted write RPCs, number of RPC retransmissions,  and  number  of
                authorization refreshes.

       NFS      Subsequent  fields:  number of handled RPCs, number of received read RPCs, number
                of received write RPCs, number of bytes read by clients, number of bytes  written
                by   clients,   number  of  RPCs  with  bad  format,  number  of  RPCs  with  bad
                authorization, number of RPCs from bad client, total number  of  handled  network
                requests,  number  of handled network requests via TCP, number of handled network
                requests via UDP, number of handled TCP connections,  number  of  hits  on  reply
                cache, number of misses on reply cache, and number of uncached requests.

       NET      First one line is produced for the upper layers of the TCP/IP stack.
                Subsequent fields: the verb "upper", number of packets received by TCP, number of
                packets transmitted by TCP, number of packets received by UDP, number of  packets
                transmitted  by  UDP,  number  of  packets  received  by  IP,  number  of packets
                transmitted by IP, number of packets delivered to higher layers by IP, and number
                of packets forwarded by IP.

                Next one line is shown for every interface.
                Subsequent  fields:  name  of  the  interface,  number of packets received by the
                interface,  number  of  bytes  received  by  the  interface,  number  of  packets
                transmitted  by  the  interface,  number  of  bytes transmitted by the interface,
                interface speed, and duplex mode (0=half, 1=full).

       IFB      Subsequent fields: name of the  InfiniBand  interface,  port  number,  number  of
                lanes,   maximum   rate  (Mbps),  number  of  bytes  received,  number  of  bytes
                transmitted, number of packets received, and number of packets transmitted.

       PRG      For every process one line is shown.
                Subsequent fields: PID (unique ID of task), name (between brackets), state,  real
                uid,  real  gid,  TGID  (group  number of related tasks/threads), total number of
                threads, exit code (in case of fatal signal: signal number  +  256),  start  time
                (epoch),  full  command line (between brackets), PPID, number of threads in state
                'running' (R), number of threads in state 'interruptible sleeping' (S), number of
                threads  in  state  'uninterruptible sleeping' (D), effective uid, effective gid,
                saved uid, saved gid, filesystem  uid,  filesystem  gid,  elapsed  time  (hertz),
                is_process  (y/n),  OpenVZ   virtual  pid  (VPID), OpenVZ container id (CTID) and
                Docker container id (CID).

       PRC      For every process one line is shown.
                Subsequent fields: PID, name (between brackets), state, total  number  of  clock-
                ticks  per  second  for  this machine, CPU-consumption in user mode (clockticks),
                CPU-consumption in system  mode  (clockticks),  nice  value,  priority,  realtime
                priority,  scheduling  policy,  current CPU, sleep average, TGID (group number of
                related tasks/threads) and is_process (y/n).

       PRE      For every process one line is shown.
                Subsequent fields: PID, name (between brackets), process state, GPU state (A  for
                active,  E  for  exited, N for no GPU user), number of GPUs used by this process,
                bitlist reflecting used GPUs, GPU busy percentage during  interval,  memory  busy
                percentage  during  interval,  memory  occupation (KiB) at this moment cumulative
                memory occupation (KiB) during interval,  and  number  of  samples  taken  during
                interval.

       PRM      For every process one line is shown.
                Subsequent  fields:  PID,  name  (between  brackets),  state,  page size for this
                machine (in bytes), virtual memory size (Kbytes), resident memory size  (Kbytes),
                shared text memory size (Kbytes), virtual memory growth (Kbytes), resident memory
                growth (Kbytes), number of minor  page  faults,  number  of  major  page  faults,
                virtual  library  exec  size  (Kbytes), virtual data size (Kbytes), virtual stack
                size  (Kbytes),  swap  space  used  (Kbytes),  TGID  (group  number  of   related
                tasks/threads),  is_process  (y/n)  and  proportional set size (Kbytes) if in 'R'
                option is specified.

       PRD      For every process one line is shown.
                Subsequent fields: PID, name (between brackets), state,  obsoleted  kernel  patch
                installed  ('n'),  standard  io  statistics used ('y' or 'n'), number of reads on
                disk, cumulative number of sectors read, number of  writes  on  disk,  cumulative
                number  of  sectors  written,  cancelled  number  of written sectors, TGID (group
                number of related tasks/threads) and is_process (y/n).
                If the standard I/O statistics (>= 2.6.20) are not used, the  disk  I/O  counters
                per process are not relevant.  The counters 'number of reads on disk' and 'number
                of writes on disk' are obsoleted anyhow.

       PRN      For every process one line is shown.
                Subsequent fields: PID, name (between brackets), state, kernel  module  'netatop'
                loaded  ('y'  or 'n'), number of TCP-packets transmitted, cumulative size of TCP-
                packets transmitted, number of TCP-packets  received,  cumulative  size  of  TCP-
                packets  received,  number  of  UDP-packets  transmitted, cumulative size of UDP-
                packets transmitted, number of UDP-packets  received,  cumulative  size  of  UDP-
                packets  transmitted,  number  of  raw  packets transmitted (obsolete, always 0),
                number of raw packets received  (obsolete,  always  0),  TGID  (group  number  of
                related tasks/threads) and is_process (y/n).

SIGNALS

       By sending the SIGUSR1 signal to pcp-atop a new sample will be forced, even if the current
       timer interval has not exceeded yet. The behavior is similar to pressing the `t` key in an
       interactive session.

       By  sending  the SIGUSR2 signal to pcp-atop a final sample will be forced after which pcp-
       atop will terminate.

EXAMPLES

       To monitor the current system load interactively with an interval of 5 seconds:

         pcp atop 5

       To monitor the system load and write it to a file (in plain ASCII) with an interval of one
       minute during half an hour with active processes sorted on memory consumption:

         pcp atop -M 60 30 > /log/pcp-atop.mem

       Store  information  about  the  system and process activity in a PCP archive folio with an
       interval of ten minutes during an hour:

         pcp atop -w /tmp/pcp-atop 600 6

       View the contents of this file interactively:

         pcp atop -r /tmp/pcp-atop

       View the processor and disk utilization of this file in parseable format:

         pcp atop -PCPU,DSK -r /tmp/pcp-atop.raw

       View the contents of today's standard logfile interactively:

         pcp atop -r

       View the contents of the standard logfile of the day before yesterday interactively:

         pcp atop -r yy

       View the contents of  the  standard  logfile  of  2014,  June  7  from  02:00  PM  onwards
       interactively:

         pcp atop -r 20140607 -b 14:00

FILES

       /etc/atoprc
            Configuration file containing system-wide default values.  See related man-page.

       ~/.atoprc
            Configuration file containing personal default values.  See related man-page.

NOTES

       pcp-atop  is  based  on  the  source code of the atop(1) command from https://atoptool.nl,
       maintained by Gerlof Langeveld (gerlof.langeveld@atoptool.nl), and aims to be command line
       and output compatible with it as much as possible.  Some features of that atop command are
       not available in pcp-atop.

       Some features of pcp-atop (such as reporting on the Apache HTTP  daemon,  Infiniband,  NFS
       client  mounts,  hardware  event  counts  and  GPU  statistics)  are only activated if the
       corresonding PCP metrics are available.  Refer to  the  documentation  for  pmdaapache(1),
       pmdainfiniband(1),   pmdanfsclient(1),  pmdanvidia(1)  and  pmdaperfevent(1)  for  further
       details on activating these metrics.

SEE ALSO

       pcp(1), pcp-atopsar(1), pmdaapache(1), pmdainfiniband(1), pmdanfsclient(1), pmdanvidia(1),
       pmdaproc(1), mkaf(1), pmlogger(1), pmlogger_daily(1), PCPIntro(1) and pcp-atoprc(5).