Provided by: pcp_6.0.5-1_amd64 bug

NAME

       pmlogger - create archive log for performance metrics

SYNOPSIS

       pmlogger  [-CLNoPruy?]   [-c conffile] [-d directory] [-h host] [-H hostname] [-I version]
       [-K spec] [-l logfile] [-m note] [-n pmnsfile] [-p pid] [-s  endsize]  [-t  interval]  [-T
       endtime] [-U username] [-v volsize] [-V version] [-x fd] archive

DESCRIPTION

       pmlogger creates the archive logs of performance metric values that may be ``played back''
       by other Performance Co-Pilot (see PCPIntro(1)) tools.  These logs form the basis  of  the
       VCR paradigm and retrospective performance analysis services common to the PCP toolkit.

       The  mandatory argument archive is the base name for the physical files that constitute an
       archive log.  The archive argument may contain strftime(3) meta-characters, which will  be
       substituted  prior  to  creating the archive log files.  When pmlogger is run as a service
       (see pmlogger_daily(1)), the standard archive base name template is %Y%m%d.%H.%M.

       The -V option specifies the version for the archive that is  generated.   By  default  the
       archive  version  $PCP_ARCHIVE_VERSION (set to 2 in current PCP releases) is used, and the
       only values currently supported for version are 2 or 3.

       Unless directed to another host by the -h option or when directly using PMDAs via  the  -o
       option, pmlogger will contact the Performance Metrics Collector Daemon (PMCD) on the local
       host and use that as the source of the metric values to be logged.

       To support the required flexibility and control over what is  logged  and  when,  pmlogger
       maintains  an  independent  two  level logging state for each instance of each performance
       metric.  At the first (mandatory) level, logging is allowed to be on (with  an  associated
       interval  between  samples),  or  off or maybe.  In the latter case, the second (advisory)
       level logging is allowed to be on (with an associated interval between samples), or off.

       The mandatory level allows universal specification that some metrics must  be  logged,  or
       must  not  be  logged.   The  default state for all instances of all metrics when pmlogger
       starts is mandatory maybe and advisory off.

       Use pmlc(1) to interrogate and change the logging state once pmlogger is running.

       If a metric's state is mandatory (on or off) and  a  request  is  made  to  change  it  to
       mandatory  maybe,  the new state is mandatory maybe and advisory off.  If a metric's state
       is already advisory (on or off) and a request is made to change it to mandatory maybe, the
       current state is retained.

       It is not possible for pmlogger to log specific instances of a metric and all instances of
       the same metric concurrently.  If specific instances are being logged and a request to log
       all  instances  is  made, then all instances of the metric will be logged according to the
       new request, superseding any prior logging request for the metric.  A request to  log  all
       instances of a metric will supersede any previous request to log all instances.  A request
       to log specific instances of a metric when all  instances  are  already  being  logged  is
       refused.   To do this one must turn off logging for all instances of the metric first.  In
       each case, the validity of the request is checked first; for example a request to change a
       metric's  logging  state  to  advisory  on  when  it  is  currently mandatory off is never
       permitted (it is necessary to change the state to mandatory maybe first).

       Optionally, each system running pmcd(1) may  also  be  configured  to  run  a  ``primary''
       pmlogger  instance.   This  pmlogger  instance is launched by $PCP_RC_DIR/pmlogger, and is
       affected         by         the          files          $PCP_SYSCONF_DIR/pmlogger/control,
       $PCP_SYSCONF_DIR/pmlogger/control.d/*,   (use   chkconfig(8),   systemctl(1)   or  similar
       platform-specific  commands  to  activate  or  disable  the  primary  pmlogger  instance),
       $PCP_SYSCONFIG_DIR/pmlogger  (environment  variable  settings  for  the  primary pmlogger)
       $PCP_SYSCONF_DIR/pmlogger/pmlogger.options (command line options  passed  to  the  primary
       pmlogger)    and    $PCP_VAR_DIR/config/pmlogger/config.default   (the   default   initial
       configuration file for the primary pmlogger).

       The primary pmlogger instance is identified by the -P option.  There may be  at  most  one
       ``primary'' pmlogger instance on each system.  The primary pmlogger instance (if any) must
       be running on the same host as the pmcd(1) to which it connects (if any), so the -h and -P
       options are mutually exclusive.

       Logging  of  some  metrics  is  possible even in the absence of a local pmcd(1), using the
       "local context" mode of operation.  This is activated using  the  -o  option,  and  causes
       pmlogger  to  make  use  of  local  DSO PMDAs instead of communicating with pmcd(1).  When
       operating using a local context, the -K option may be used to control the DSO  PMDAs  that
       should  be  made  accessible.   The  spec  argument  conforms  to  the syntax described in
       pmSpecLocalPMDA(3).  More than one -K option may be used.

       When  launched  as  a  non-primary  instance,  pmlogger  will  exit  immediately  if   the
       configuration file causes no metric logging to be scheduled.  The -L option overrides this
       behavior, and causes a non-primary pmlogger instance  to  ``linger'',  presumably  pending
       some  future  dynamic  re-configuration  and state change via pmlc(1).  pmlogger will also
       linger without the -L option being used if all the metrics to be logged are logged as once
       only  metrics.   When  the  once  only metrics have been logged, a warning message will be
       generated stating that the event queue is empty and no more events will be scheduled.

       By default all diagnostics and errors from pmlogger are written to the  file  pmlogger.log
       in  the  directory  where pmlogger is launched.  The -l option may be used to override the
       default behavior.  If the log file cannot be created or is not writable, output is written
       to  standard  error instead.  If the logfile for the -l option is "-" (i.e.  -l-) then log
       messages are written to the standard output stream.  This can be particularly useful  when
       running pmlogger manually, rather than as a service daemon.

       The  -N option directs pmlogger to notify a service manager, typically systemd(1), when it
       has started and is about to begin writing  PCP  archive  logs.   This  option  would  only
       normally  be  used when pmlogger is run as a daemon service under the control of a service
       manager.  For more details, see __pmServerNotifyServiceManagerReady(3) and systemd(1).  On
       platforms  that do not use a service manager that supports notifications, the -N option is
       basically a no-op.

       If specified, the -s option instructs pmlogger  to  terminate  after  a  certain  size  in
       records,  bytes or time units has been accumulated.  If endsize is an integer then endsize
       records will be written to the log.  If endsize is an integer suffixed by b or bytes  then
       endsize  bytes  of  the  archive data will be written out (note, however, that archive log
       record boundaries will not be broken and so this limit may be slightly surpassed).   Other
       viable  file size units include: K, Kb, KiB, Kbyte, Kilobyte for kilobytes and M, Mb, MiB,
       Mbyte, Megabyte for megabytes and G, Gb, GiB, Gbyte, Gigabyte for gigabytes.  These  units
       may be optionally suffixed by an s and may be of mixed case.  Alternatively endsize may be
       an integer or a floating  point  number  suffixed  using  a  time  unit  as  described  in
       PCPIntro(1) for the interval argument (to the standard PCP -t command line option).
       Some examples of different formats:
          -s 100
          -s 100bytes
          -s 100K
          -s 100Mb
          -s 10Gbyte
          -s 10mins
          -s 1.5hours
       The default is for pmlogger to run forever.

       The  -r option causes the size of the physical record(s) for each group of metrics and the
       expected contribution of the group to the size of the PCP archive  for  one  full  day  of
       collection  to  be  reported in the log file.  This information is reported the first time
       each group is successfully written to the archive.

       The -U option specifies the user account under which to run pmlogger.  The default is  the
       current  user  account  for interactive use.  When run as a daemon, the unprivileged "pcp"
       account is used in current versions of PCP, but in older versions  the  superuser  account
       ("root") was used by default.

       The  log file is potentially a multi-volume data set, and the -v option causes pmlogger to
       start a new volume after a certain  size  in  records,  bytes,  or  time  units  has  been
       accumulated for the current volume.  The format of this size specification is identical to
       that of the -s option (see above).  The default is for pmlogger to create a single  volume
       log.  Additional volume switches can also be forced asynchronously by either using pmlc(1)
       or sending pmlogger a SIGHUP signal (see below).  Note, if a scheduled volume switch is in
       operation  due  to  the  -v  option, then its counters will be reset after an asynchronous
       switch.

       Independent of any -v option, each volume of an archive is limited to no  more  than  2^31
       bytes,  so  pmlogger  will  automatically  create a new volume for the archive before this
       limit is reached.

       Normally pmlogger operates on the  distributed  Performance  Metrics  Name  Space  (PMNS),
       however  if  the  -n option is specified an alternative local PMNS is loaded from the file
       pmnsfile.

       Under normal circumstances, pmlogger will run  forever  (except  for  a  -s  option  or  a
       termination  signal).   The  -T  option  may be used to limit the execution time using the
       format of time as prescribed by PCPIntro(1).  The time is interpreted within the time zone
       of the PMCD server, unless the -y option is given, within which case the time zone at this
       logger host is used.
       Some examples of different formats:
          -T 10mins
          -T '@ 11:30'
       From this it can be seen that -T 10mins and -s 10mins perform identical actions.

       Alternatively, pmlogger runtime may be limited to the lifetime of another process by using
       the  -p  or --PID option to nominate the PID of the process of interest.  In this case the
       pmlogger will exit when the other process no longer exists.

       When pmlogger receives a SIGHUP signal, the current volume of the log is closed, and a new
       volume  is  opened.  This mechanism (or the alternative mechanism via pmlc(1)) may be used
       to manage the growth of the log files - once a log volume is  closed,  that  file  may  be
       archived  without  ill-effect  on  the  continued  operation of pmlogger.  See also the -v
       option above.

       When pmlogger receives a SIGUSR2 signal, the current archive log  is  closed,  and  a  new
       archive  is  opened.   For  this  to  succeed,  the original archive argument must include
       strftime(3) meta characters (e.g.  %Y%m%d.%H.%M), otherwise pmlogger will exit because the
       archive  files will already exist and pmlogger will not over-write existing archive files.
       Note that SIGUSR2 triggers pmlogger to re-exec itself and re-parse all original arguments.
       This means that any relative time limits placed on it's termination time or sampling limit
       are reset and begin again.  This only affects relative  termination  times,  not  absolute
       times e.g.  -T 5s is affected, but -T 5pm is not.

       Historically  the  buffers  for  the  current  log  may be flushed to disk using the flush
       command of pmlc(1), or by using the -u option.  The current version of  pmlogger  and  the
       libpcp  routines that underpin pmlogger unconditionally use unbuffered writes and a single
       fwrite(3) for each logical  record  written,  and  so  ``flushing''  does  not  force  any
       additional  data  to  be  written to the file system.  The -u option and the pmlc(1) flush
       command are retained for backwards compatibility.

       When launched with the -x option, pmlogger will accept asynchronous  control  requests  on
       the  file  descriptor  fd.   This  option  is  only  expected to be used internally by PCP
       applications that support ``live record mode''.

       The -m option allows the string note to be appended to the map file for this  instance  of
       pmlogger  in  the  $PCP_TMP_DIR/pmlogger  directory.  This is currently used internally to
       document the file descriptor (fd) when the -x option is used, or  to  indicate  that  this
       pmlogger  instance was started under the control of pmlogger_check(1), (-m pmlogger_check)
       or was re-exec'd (see execvp(3)) due to a SIGUSR2 signal being recieved as described above
       (-m reexec).

       The  -H  option allows the hostname written into the archive label to be overridden.  This
       mirrors the -H option of pmcd(1) , but allows it to be specified on the pmlogger  process.
       Without this option, the value returned from the logged pmcd(1) is used.

       The  -C  option will cause the configuration file to be parsed and pmlogger will then exit
       without creating an output archive, so when -C is  specified,  the  archive  command  line
       argument is not required.  Any errors in the configuration file are reported.

       The -d or --directory option may be used to specify the directory where the archive should
       be created.  directory may include sh(1) metacharacters, like $(...)  or `...` or $var and
       pmlogger  will expand these to produce a final directory path.  The resultant path must be
       absolute, not relative.  The -d option is intended primarily for use by  pmlogger_check(1)
       and  normal users would not typically need to use the option, as the directory for archive
       is either implied by  archive  if  it  contains  directory  components  else  the  current
       directory by default.

CONFIGURATION FILE SYNTAX

       The  configuration  file may be specified with the -c option.  If it is not, configuration
       specifications are read from standard input.

       If   conffile   does   not   exist,   then   a   search   is   made   in   the   directory
       $PCP_VAR_DIR/config/pmlogger  for a file of the same name, and if found that file is used,
       e.g.  if  config.mumble  does  not  exist  in  the  current   directory   and   the   file
       $PCP_VAR_DIR/config/pmlogger/config.mumble  does  exist,  then  -c  config.mumble  and  -c
       $PCP_VAR_DIR/config/pmlogger/config.mumble are equivalent.

       The syntax for the configuration file is as follows.

       1.   Words are separated by white space (space, tab or newline).

       2.   The symbol ``#'' (hash) introduces a comment, and all text up to the next newline  is
            ignored.

       3.   Keywords (shown in bold below) must appear literally (i.e. in lower case).

       4.   Each  specification  begins  with  the  optional  keyword log, followed by one of the
            states mandatory on, mandatory off, mandatory maybe, advisory on or advisory off.

       5.   For the on states, a logging interval must  follow  using  the  syntax  ``once'',  or
            ``default'',  or  ``every N timeunits'', or simply ``N timeunits'' - N is an unsigned
            integer, and timeunits is one of the keywords msec, millisecond,  sec,  second,  min,
            minute, hour or the plural form of one of the above.
            Internal  limitations  require  the  interval  to  be smaller than (approximately) 74
            hours.  An interval value of zero is a synonym for  once.   An  interval  of  default
            means  to  use  the default logging interval of 60 seconds; this default value may be
            changed to interval with the -t command line option.

            The interval argument follows  the  syntax  described  in  PCPIntro(1),  and  in  the
            simplest  form  may  be  an  unsigned  integer  (the  implied  units in this case are
            seconds).

       6.   Following the state and possible interval specifications comes a ``{'', followed by a
            list  of  one  or  more metric specifications and a closing ``}''.  The list is white
            space (or comma) separated.  If there is only one metric specification in  the  list,
            the braces are optional.

       7.   A  metric  specification  consists  of  a metric name optionally followed by a set of
            instance names.  The metric name follows the standard  PCP  naming  conventions,  see
            PMNS(5),  and  if  the metric name is a non-leaf node in the PMNS (see PMNS(5)), then
            pmlogger will recursively descend the PMNS and apply the logging specification to all
            descendent  metric  names that are leaf nodes in the PMNS.  The set of instance names
            is a ``['', followed by a list of one or  more  space  (or  comma)  separated  names,
            numbers  or  strings, and a closing ``]''.  Elements in the list that are numbers are
            assumed to be internal  instance  identifiers,  other  elements  are  assumed  to  be
            external instance identifiers - see pmGetInDom(3) for more information.

            If no instances are given, then the logging specification is applied to all instances
            of the associated metric.

       8.   There may be an arbitrary number of logging specifications.

       9.   As of PCP version 4.0 and later, any metric name specification that does not  resolve
            to  a  leaf node in the PMNS is added to an internal list of possible dynamic subtree
            roots.  PMDAs can dynamically create new metrics below a dynamic root node  in  their
            PMNS,   and   send  a  notification  to  clients  that  the  PMNS  has  changed,  see
            pmdaExtSetFlags(3) and in particular the METRIC  CHANGES  section  for  API  details.
            This  mechanism  is currently supported by pmdaopenmetrics(1) and pmdammv(1).  When a
            fetch issued by pmlogger returns with the PMDA_EXT_NAMES_CHANGE  flag  set,  pmlogger
            will  traverse  the  internal  list of possible dynamic subtree nodes and dynamically
            discover any new metrics.  In effect, as of PCP version 4.0 and later,  pmlogger  can
            be  configured  to  dynamically  log new metrics that appear in the future, after the
            configuration file is initially parsed.

       10.  Following all of the logging specifications, there may be an optional access  control
            section,  introduced  by  the literal token [access].  Thereafter come access control
            rules that allow or disallow operations from particular hosts or groups of hosts.

            The operations may be used to interrogate or control a running pmlogger using pmlc(1)
            and fall into the following classes:

            enquire        interrogate the status of pmlogger and the metrics it is logging
            advisory       Change advisory logging.
            mandatory      Change mandatory logging.
            all            All of the above.

            Access  control  rules  are  of  the  form  ``allow  hostlist : operationlist ;'' and
            ``disallow hostlist : operationlist ;''.

            The hostlist follows the syntax and semantics for the access control mechanisms  used
            by  PMCD and are fully documented in pmcd(1).  An operationslist is a comma separated
            list of the operations advisory, mandatory, enquire and all.

            A missing [access] section allows all access and is equivalent to allow * : all;.

       The configuration (either from  standard  input  or  conffile)  is  initially  scanned  by
       pmcpp(1)  with  the  options  -rs  and  -I $PCP_VAR_DIR/config/pmlogger.  This extends the
       configuration file syntax with include file processing (%include), a  common  location  to
       search  for  include  files  ($PCP_VAR_DIR/config/pmlogger),  macro definitions (%define),
       macro expansion (%name and %{name}) and conditional inclusion of lines  (%ifdef  name  ...
       %else ... %endif and %ifndef name ... %else ... %endif).

OPTIONS

       The available command line options are:

       -c conffile, --config=conffile
            Specify the conffile file to use.

       -C, --check
            Parse configuration and exit.

       -h host, --host=host
            Fetch  performance  metrics  from  pmcd(1)  on  host,  rather  than  from the default
            localhost.

       -H hostname, --labelhost=hostname
            Specify the hostname to use instead of the one returned by pmcd(1).

       -I version, --pmlc-ipc-version=version
            Normally, pmlogger and pmlc(1) will autonegotiate a mutually acceptable  version  for
            their  private  IPC  channel.  Use -I to force pmlogger to offer (at most) version as
            the version to be used.  This option may be required if pmlogger needs to be  managed
            by an older version of pmlc(1) that fails to autonegotiate correctly.

       -K spec, --spec-local=spec
            When  fetching  metrics  from  a local context (see -o), the -K option may be used to
            control the DSO PMDAs that should be made accessible.  The spec argument conforms  to
            the syntax described in pmSpecLocalPMDA(3).  More than one -K option may be used.

       -l logfile, --log=logfile
            Write all diagnostics to logfile instead of the default pmlogger.log.

       -L, --linger
            Run even if not the primary logger instance and nothing to log.

       -m note, --note=note
            Append note to the port map file for this instance.

       -n pmnsfile, --namespace=pmnsfile
            Load an alternative Performance Metrics Name Space (PMNS(5)) from the file pmnsfile.

       -N, --notify
            Notify service manager such as systemd(1) as needed.

       -o, --local-PMDA
            Use a local context to collect metrics from DSO PMDAs on the local host without PMCD.
            See also -K.

       -p PID, --PID=PID
            Log specified metrics for the lifetime of the pid PID.

       -P, --primary
            Run as primary logger instance.  See above for more detailed description of this.

       -r, --report
            Report record sizes and archive growth rate.

       -s endsize, --size=endsize
            Terminate after log size exceeds endsize.

       -t interval, --interval=interval
            Specify the logging interval.  The default value is 60 seconds.  Please refer to  the
            ENVIRONMENT  and  FILES  sections  below  regarding the PMLOGGER_INTERVAL environment
            variable and its impact on the default logging interval.

       -T endtime, --finish=endtime
            Specify the endtime when to end logging.

       -u   Use unbuffered output.  This is the default (so this option does nothing).

       -U username, --username=username
            When in daemon mode, run as user username.

       -v volsize, --volsize=volsize
            Switch log volumes after reaching log volume size volsize.

       -V version, --version=version
            Specify log archive version.  The default and the only accepted value is 2.

       -x fd
            Allow asynchronous control requests on the file descriptor fd.

       -y   Use local timezone instead of the timezone from the pmcd(1) host.

       -?, --help
            Display usage message and exit.

EXAMPLES

       For each PCP utility, there is a sample pmlogger configuration file that could be used  to
       create  an  archive  log  suitable  for replaying with that tool (i.e. includes all of the
       performance metrics used by the tool).  For a tool named foo this  configuration  file  is
       located in $PCP_VAR_DIR/config/pmlogger/config.foo.

       The  following is a simple default configuration file for a primary pmlogger instance, and
       demonstrates most of the capabilities of the configuration specification language.

            log mandatory on once { hinv.ncpu hinv.ndisk }
            log mandatory on every 10 minutes {
                disk.all.write
                disk.all.read
                network.interface.in.packets [ "et0" ]
                network.interface.out.packets [ "et0" ]
                nfs.server.reqs [ "lookup" "getattr" "read" "write" ]
            }

            log advisory on every 30 minutes {
                environ.temp
                pmcd.pdu_in.total
                pmcd.pdu_out.total
            }

            %include "macros.default"

            %ifdef %disk_detail
            log mandatory on %disk_detail_freq {
                disk.dev
            }
            %endif

            [access]
            disallow * : all except enquire;
            allow localhost : mandatory, advisory;

HOSTNAME CHANGES

       The hostname of the PMCD that is providing metrics to pmlogger is used in several ways.

       PMCD's hostname (or the argument from the -H option) is included in the archive label  and
       may   be   used   to   ensure  that  subsequent  operations  on  multiple  archives,  e.g.
       pmlogextract(1), are only applied to archives from the same host.

       For  pmlogger  instances  using  a  local  PMCD  that  are   launched   and   managed   by
       pmlogger_check(1)  and  pmlogger_daily(1), (or the systemd(1) or cron(8) services that use
       these scripts), the local hostname may also be used to construct the name of  a  directory
       where all the archives for the one host are stored, e.g. $PCP_ARCHIVE_DIR/<hostname>.

       And  PMCD's  hostname  is also stored in the archive via the pmcd.pmlogger.hostname metric
       that is used as part of the checks to ensure that there is continuity of performance  data
       after the nightly archive rotation by pmlogger_daily(1).

       The hostname of the PMCD host may change during boot time when the system transitions from
       a temporary hostname to a  persistent  hostname,  or  by  explicit  administrative  action
       anytime  after  the  system has been booted.  When this happens, pmlogger may need to take
       special action, specifically if the pmlogger instance was launched from  pmlogger_check(1)
       or  pmlogger_daily(1),  then pmlogger must exit.  Under normal circumstances systemd(1) or
       cron(8) will launch a new pmlogger shortly thereafter, and this new pmlogger instance will
       be operating in the context of the new hostname for the host where PMCD is running.

DIAGNOSTICS

       The  archive  logs  are  sufficiently precious that pmlogger will not truncate an existing
       physical file.  A message of the form
        ...: "foo.index" already exists, not over-written
        ...: File exists
       indicates this situation has arisen.  You must explicitly  remove  the  files  and  launch
       pmlogger again.

       There  may be at most one primary pmlogger instance per monitored host; attempting to bend
       this rule produces the error:
        pmlogger: there is already a primary pmlogger running

       Various  other  messages  relating  to  the  creation  and/or   deletion   of   files   in
       $PCP_TMP_DIR/pmlogger  suggest a permission problem on this directory, or some feral files
       have appeared therein.

FILES

       archive.meta
            metadata (metric descriptions, instance domains, etc.) for the archive log

       archive.0
            initial volume of metrics values (subsequent volumes have suffixes 1, 2, ...)

       archive.index
            temporal index to support rapid random access to the other files in the archive log

       $PCP_TMP_DIR/pmlogger
            pmlogger maintains the files in this directory as the map between the process  id  of
            the  pmlogger  instance  and  the  IPC port that may be used to control each pmlogger
            instance (as used by pmlc(1))

       $PCP_VAR_DIR/config/pmlogger/config.default
            default  configuration  file  for  the  primary   logger   instance   launched   from
            $PCP_RC_DIR/pmlogger

       $PCP_VAR_DIR/config/pmlogger/config.*
            assorted  configuration  files  suitable  for  creating logs that may be subsequently
            replayed with the PCP visualization and monitoring tools

       $PCP_ARCHIVE_DIR/<hostname>
            Default directory for PCP archive files for performance metric values collected  from
            the host <hostname>.

       $PCP_SYSCONFIG_DIR/pmlogger
            additional  environment variables that will be set when the primary pmlogger instance
            executes.  Only settings of the form "PMLOGGER_VARIABLE=value" will be honoured.

       ./pmlogger.log
            (or $PCP_ARCHIVE_DIR/<hostname>/pmlogger.log when  started  automatically  by  either
            $PCP_RC_DIR/pmlogger   or   one   of  the  pmlogger(1)  monitoring  scripts  such  as
            pmlogger_check(1))
            all messages and diagnostics are directed here

ENVIRONMENT

       Normally pmlogger creates a socket to receive control messages from pmlc(1) on  the  first
       available TCP/IP port numbered 4330 or higher.  The environment variable PMLOGGER_PORT may
       be used to specify an alternative starting port number.

       If set to the value 1, the PMLOGGER_LOCAL environment variable will cause pmlogger to  run
       in a localhost-only mode of operation, where it binds only to the loopback interface.

       The  PMLOGGER_REQUEST_TIMEOUT  variable  may  be  set  by  applications such as pmlc(1) to
       specify a timeout in seconds for connection requests to the pmlogger control port.  If not
       set,  connections  may  block  indefinitely.   This  variable would not normally be set by
       pmlogger itself.

       The PMLOGGER_MAXPENDING variable can be set to indicate the maximum length  to  which  the
       queue of pending pmlc connections may grow.

       The  default  sampling  interval  used  by pmlogger can be set using the PMLOGGER_INTERVAL
       variable (if not set, 60 seconds will be used).  Both the command line and  directives  in
       the configuration file will override this value.  It is an integer in units of seconds.

       On  platforms  using  systemd(1),  and  when  the  -N  option  is given, the NOTIFY_SOCKET
       environment variable would normally be set by  the  service  manager  prior  to  launching
       pmlogger.

PCP ENVIRONMENT

       Environment variables with the prefix PCP_ are used to parameterize the file and directory
       names used by PCP.  On each installation, the file /etc/pcp.conf contains the local values
       for  these  variables.   The  $PCP_CONF  variable  may  be  used to specify an alternative
       configuration file, as described in pcp.conf(5).

SEE ALSO

       PCPIntro(1),  pmcd(1),  pmdumplog(1),   pmlc(1),   pmlogger_check(1),   pmlogger_daily(1),
       systemctl(1),  systemd(1),  execvp(3),  PMAPI(3),  __pmServerNotifyServiceManagerReady(3),
       pmSpecLocalPMDA(3),   strftime(3),   pcp.conf(5),   pcp.env(5),   pmlogger(5),    PMNS(5),
       chkconfig(8) and cron(8).