pmdapostgresql(1) — Linux manual page


PMDAPOSTGRESQL(1)          General Commands Manual         PMDAPOSTGRESQL(1)

NAME         top

       pmdapostgresql - PostgreSQL database PMDA

DESCRIPTION         top

       pmdapostgresql is a Performance Co-Pilot (PCP) Performance Metrics
       Domain Agent (PMDA) which extracts live performance data from a
       running PostgreSQL database server.

       Many of the statistics available from a PostgreSQL server may not be
       enabled by default.  Refer to the online documentation 
       which describes each of the available parameters related to
       statistics collection and how to enable them.


       pmdapostgresql reads a mandatory ini-style configuration file:


       This file currently contains only one section [authentication] which
       specifies values for the following settings (their default values are
       shown in parenthesis):

       host (local)   Hostname to connect to.

       port (5432)    Port number to use.

       dbname (postgres)
                      Database name.

       username (postgres)
                      Username to run as and to connect to the database.

       password (password)
                      Password to connect to the database.

       osuser (unset) Operating system user the PMDA runs as.

       The defaults (as above) will result in the PMDA running as the
       current user, using a UNIX domain socket connection to the PostgreSQL
       server on the localhost.

       If osuser is not specified in the configuration file, the PMDA will
       run as the current user.  A host specification of local will use a
       UNIX domain socket, which uses peer authentication, see comments in
       the pg_hba.conf file.  In this case, the osuser setting should
       probably be set to postgres.

       It is generally not necessary to alter the default configuration file
       for monitoring the local PostgreSQL server instance with a default
       server configuration.  Note that the port number is required even for
       a UNIX domain connection because it's used as the socket filename by
       the server.

INSTALLATION         top

       To install, the following must be done as root:

           # cd $PCP_PMDAS_DIR/postgresql
           # ./Install

       To uninstall, the following must be done as root:

           # cd $PCP_PMDAS_DIR/postgresql
           # ./Remove

       pmdapostgresql is launched by pmcd(1) and should never be executed
       directly.  The Install and Remove scripts notify pmcd(1) when the
       agent is installed or removed.

       pmdapostgresql will automatically attempt to reconnect to the
       PostgreSQL server if its connection is lost - e.g. if the PostgreSQL
       service is restarted.


       This version of pmdapostgresql has been tested and verified with
       PostgreSQL server version 10.2 and earlier.  Later versions will
       probably also work correctly because the PMDA probes the various
       performance tables on start-up to determine the column ordering.  It
       also tolerates missing or renamed tables and/or columns.

FILES         top

            configuration file for the pmdapostgresql agent

            installation script for the pmdapostgresql agent

            undo installation script for the pmdapostgresql agent

            default log file for messages from the pmdapostgresql agent

       Note that the usual/default value for $PCP_PMDAS_DIR is
       /var/lib/pcp/pmdas and the default for $PCP_LOG_DIR is /var/log/pcp
       but these settings are platform dependent.


       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         top

       PCPIntro(1), pmcd(1) and .

COLOPHON         top

       This page is part of the PCP (Performance Co-Pilot) project.
       Information about the project can be found at ⟨⟩.
       If you have a bug report for this manual page, send it to  This page was obtained from the project's upstream
       Git repository ⟨⟩ on
       2020-08-13.  (At that time, the date of the most recent commit that
       was found in the repository was 2020-08-11.)  If you discover any
       rendering problems in this HTML version of the page, or you believe
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       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

Performance Co-Pilot                 PCP                   PMDAPOSTGRESQL(1)