Provided by: pcp_4.3.1-1_amd64 bug

NAME

       pmlogger - create archive log for performance metrics

SYNOPSIS

       pmlogger  [-CLoPruy]  [-c  configfile]  [-h host] [-H hostname] [-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 -V option specifies the version for the archive  that  is  generated.   By  default  a
       version 2 archive is generated, and the only value currently supported for version is 2.

       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 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.

       Historically the buffers for the current log may  be  flushed  to  disk  using  the  flush
       command  of  pmlc(1),  or  by sending pmlogger a SIGUSR1 signal 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, the SIGUSR1 handling 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).

       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.

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  configfile  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 pmdaprometheus(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  configfile)  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).

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;

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_LOG_DIR/pmlogger/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_LOG_DIR/pmlogger/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_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.

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),    systemctl(1),
       pmSpecLocalPMDA(3), pcp.conf(5), pcp.env(5), pmlogger(5), pmns(5) and chkconfig(8).

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.