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).