NAME

       pmdaroot - a privileged PMCD helper performance metrics domain agent

SYNOPSIS

       $PCP_PMDAS_DIR/root/pmdaroot [-d domain] [-l logfile] [-s sockname]

DESCRIPTION

       pmdaroot  is  a special Performance Metrics Domain Agent (PMDA) which cooperates closely with pmcd(1) and
       other PMDAs to provide limited privileged services to these unprivileged processes.

       In this role it is used to discover operating system containers running  on  the  local  host.   It  also
       enables  access to performance data from within those containers by other PMDAs running on the bare-metal
       host, using the pmdaRootConnect(3) and the associated namespace interfaces.

       Like all other PMDAs, it also exports performance metrics from the domain it controls.   Currently,  this
       is  limited  to information about the containers on the local system; currently Docker and LXC containers
       can be detected.

       If a non-default Docker parent-cgroup name is being used, this value can be indicated to pmdaroot through
       addition of a $PCP_SYSTEMD_CGROUP variable in /etc/pcp.conf.

       -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 root.log is written in the current directory
            of pmcd(1) when pmdaroot 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.

       -s   Location  of the unix(7) domain socket for communication with clients seeking privileged operations.
            By default, a socket file named $PCP_TMP_DIR/pmcd/root.socket is used.

INSTALLATION

       Access to the names, help text and values for the kernel performance metrics is available  by  default  -
       unlike most other agents, no action is required to enable them and they should not be removed.

FILES

       $PCP_PMDAS_DIR/root/help
                 default help text file for metrics exported by the root PMDA.
       $PCP_LOG_DIR/pmcd/root.log
                 default log file for error messages and other information from the root PMDA.
       $PCP_TMP_DIR/pmcd/root.socket
                 default socket file for communication with root PMDA clients.

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), PMDA(3), pmdaRootConnect(3), pcp.conf(5) and unix(7).