pmdaoverhead(1) — Linux manual page


PMDAOVERHEAD(1)          General Commands Manual         PMDAOVERHEAD(1)

NAME         top

       pmdaoverhead - performance metrics domain agent (PMDA) exporting
       resource consumption metrics for groups of processes

SYNOPSIS         top

       $PCP_PMDAS_DIR/overhead/pmdaoverhead [-C] [-c config] [-d domain]
       [-l logfile] [-R interval]

DESCRIPTION         top

       pmdaoverhead is a configurable Performance Metrics Domain Agent
       (PMDA) for exporting resource consumption for groups of related

       The pmdaoverhead command line options are:

       -C  parse the configuration file(s) and exit after reporting any

       -c  configuration file(s), config may be either a file or a
           directory; in the latter case all the files within config are
           assumed to be configuration files for pmdaoverhead and they
           will all be processed.

           Each configuration file defines one or more ``groups'' of
           processes of interest, using the syntax described in the
           ``CONFIGURATION'' section below.

           By default all configuration files below the
           $PCP_SYSCONF_DIR/overhead/conf.d/ directory are used.

       -d  It is absolutely crucial that the performance metrics domain
           number specified here is unique and consistent.  That is,
           domain should be different for every PMDA on the one host,
           and the same domain number should be used for the same PMDA
           on all hosts.

       -l  Location of the log file.  By default, a log file named
           overhead.log is written in the current directory of pmcd(1)
           when pmdaoverhead is started, i.e.  $PCP_LOG_DIR/pmcd.  If
           the log file cannot be created or is not writable, output is
           written to the standard error instead.

       -R  The PMDA uses a separate thread to periodically scan all
           processes to determine which processes are deemed
           ``interesting'' in each group, and extracting resource
           consumption for those processes.  The interval (in seconds)
           determines how often this scanning and resource calculation
           is done, the default is 60 (seconds).


       Each configuration file defines one or more ``groups'' of
       processes.  The file format is simple and follows the following

       1.  Lines beginning with a hash ``#'' are treated as comments.
           More generally, except for the pattern: clause described
           below, all text between a hash and the end of line is treated
           as a comment.

       2.  White space (spaces or tabs or newlines) are required to
           separate lexical components.  Spaces and tabs are otherwise
           ignored.  Other than terminating comments and the regex in a
           pattern: clause, newlines are also ignored.

       3.  Each group is introduced by a group clause that has the form
                   group name { parameters }
           where name is a unique name for the group across all groups
           in the pmdaoverhead configuration files.  As name becomes
           embedded in the Performance Metrics Name Space (PMNS) if must
           follow the rules for metric name components as described in
           PMNS(5), namely beginning with an alphabetic character,
           followed by zero or more characters drawn from the
           alphabetics, numerics and the underscore ``_'' character.

       4.  The parameters must include one id: clause and one pattern:

       5.  An id: clause has the form
                   id: ident
           where ident is a unique identifier number for the group
           across all groups in the pmdaoverhead configuration files.
           Valid values for ident are in the range 0 to 4094

       6.  A pattern: clause has the form
                   pattern: regex
           where regex is an extended regular expression notation in the
           style of egrep(1).  The regex starts at the first non-
           whitespace character after pattern: and extends to the next

           The processes that are considered to be members of the group
           are those for which the command name, as reported by
                   $ pminfo -f proc.psinfo.cmd
           is matched by regex plus all the descendents of those
           processes.  So for example the regex ^pmcd$ will match
           pmcd(1) and all the PMDA processes launched by pmcd(1) and
           any of their children, etc.

INSTALLATION         top

       If you want access to the names, help text and values for the
       overhead performance metrics, do the following as root:

            # cd $PCP_PMDAS_DIR/overhead
            # ./Install

       If you want to undo the installation, do the following as root:

            # cd $PCP_PMDAS_DIR/overhead
            # ./Remove

       pmdaoverhead is launched by pmcd and should never be executed
       directly.  The Install and Remove scripts notify pmcd when the
       agent is installed or removed.

FILES         top

              command line options used to launch pmdaoverhead
              installation script for the pmdaoverhead agent
              undo installation script for the pmdaoverhead agent
              default log file for error messages and other information
              from pmdaoverhead
              directory containing configuration files for the overhead


       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

SEE ALSO         top

       PCPIntro(1), pmcd(1), pmdaproc(1), pcp.conf(5), pcp.env(5) and

COLOPHON         top

       This page is part of the PCP (Performance Co-Pilot) project.
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       page, send it to  This page was obtained from the
       project's upstream Git repository
       ⟨⟩ on 2023-12-22.
       (At that time, the date of the most recent commit that was found
       in the repository was 2023-12-16.)  If you discover any rendering
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Performance Co-Pilot               PCP                   PMDAOVERHEAD(1)