1PMDAROOT(1) General Commands Manual PMDAROOT(1)
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6 pmdaroot - a privileged PMCD helper performance metrics domain agent
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9 $PCP_PMDAS_DIR/root/pmdaroot [-d domain] [-l logfile] [-s sockname]
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12 pmdaroot is a special Performance Metrics Domain Agent (PMDA) which co‐
13 operates closely with pmcd(1) and other PMDAs to provide limited privi‐
14 leged services to these unprivileged processes.
15 In this role it is used to discover operating system containers running
17 on the local host. It also enables access to performance data from
18 within those containers by other PMDAs running on the bare-metal host,
19 using the pmdaRootConnect(3) and the associated namespace interfaces.
20 Like all other PMDAs, it also exports performance metrics from the do‐
22 main it controls. Currently, this is limited to information about the
23 containers on the local system; currently Docker and LXC containers can
24 be detected.
25 If a non-default Docker parent-cgroup name is being used, this value
27 can be indicated to pmdaroot through addition of a $PCP_SYSTEMD_CGROUP
28 variable in /etc/pcp.conf.
29 -d It is absolutely crucial that the performance metrics domain num‐
31 ber specified here is unique and consistent. That is, domain
32 should be different for every PMDA on the one host, and the same
33 domain number should be used for the same PMDA on all hosts.
34 -l Location of the log file. By default, a log file named root.log
36 is written in the current directory of pmcd(1) when pmdaroot is
37 started, i.e. $PCP_LOG_DIR/pmcd. If the log file cannot be cre‐
38 ated or is not writable, output is written to the standard error
39 instead.
40 -s Location of the unix(7) domain socket for communication with
42 clients seeking privileged operations. By default, a socket file
43 named $PCP_TMP_DIR/pmcd/root.socket is used.
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46 Access to the names, help text and values for the kernel performance
47 metrics is available by default - unlike most other agents, no action
48 is required to enable them and they should not be removed.
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51 $PCP_PMDAS_DIR/root/help
52 default help text file for metrics exported by the root PMDA.
53 $PCP_LOG_DIR/pmcd/root.log
54 default log file for error messages and other information
55 from the root PMDA.
56 $PCP_VAR_DIR/pmcd/root.socket
57 default socket file for communication with root PMDA clients.
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60 Environment variables with the prefix PCP_ are used to parameterize the
61 file and directory names used by PCP. On each installation, the file
62 /etc/pcp.conf contains the local values for these variables. The
63 $PCP_CONF variable may be used to specify an alternative configuration
64 file, as described in pcp.conf(5).
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67 PCPIntro(1), pmcd(1), PMDA(3), pmdaRootConnect(3), pcp.conf(5) and
68 unix(7).
69Performance Co-Pilot PCP PMDAROOT(1)