Ubuntu Manpage: pmdapostgresql - PostgreSQL database PMDA

NAME

       pmdapostgresql - PostgreSQL database PMDA

DESCRIPTION

       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 https://www.postgresql.org/docs/current/static/monitoring-stats.html which describes
       each of the available parameters related to statistics collection and how to enable them.

CONFIGURATION

pmdapostgresql reads a mandatory ini-style configuration file:

$PCP_PMDAS_DIR/postgresql/postgresql.conf

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

       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.

SUPPORTED VERSIONS

       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

       $PCP_PMDAS_DIR/postgresql/pmdapostgresql.conf
            configuration file for the pmdapostgresql agent

       $PCP_PMDAS_DIR/postgresql/Install
            installation script for the pmdapostgresql agent

       $PCP_PMDAS_DIR/postgresql/Remove
            undo installation script for the pmdapostgresql agent

       $PCP_LOG_DIR/pmcd/postgresql.log
            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.

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).