pmdaperfevent is a Performance Metrics Domain Agent (PMDA) that
configures and reads the hardware performance counters using the
Linux kernel perf_event API.
The perfevent PMDA exports metrics for hardware performance counters
that are configurable from the Linux kernel perf_event API. The PMDA
uses the libpfm4 library to access the hardware performance counters
so any counters that are supported in libpfm4 should be available.
Also included is the ability to read the Intel RAPL counters via
direct MSR access. The PMDA supports automatically loading different
counters for each hardware architecture. A single configuration file
is used to specify the desired counters for each hardware performance
monitoring unit (PMU). The configuration file allows different
counters to be programmed on different CPUs and supports round-robin
assignment of uncore counters needed for some AMD chips.
The PMDA also counts for events exposed in the kernel via
/sys/bus/event_source/devices directory. The PMU device name and the
event name must be mentioned in the configuration file. Otherwise,
the metric won't be available to monitor through this PMDA.
The PMDA configures the counters to count events in both user and
kernel mode. This means that the hardware counters are unavailable
to use by normal unprivileged user applications when they are in use
by the PMDA. The PMDA provides a mechanism to temporarily disable
the system-wide counters in order to allow normal users to be able to
use the counters if they wish. See perfalloc(1) for details.
Note that pmdaperfevent is affected by the value of the
kernel.perf_event_paranoid setting, which can be adjusted by
A brief description of the pmdaperfevent command line options
-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
perfevent.log is written in the current directory of pmcd(1)
when pmdaperfevent 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.
-U User account under which to run the agent. The default is the
privileged "root" account.
-i listen on given port number for connection from pmcd(1)-p communicate with pmcd(1) via stdin/stdout
-u expect pmcd(1) to connect on given unix domain socket
-6 expect pmcd(1) to connect on given ipv6 port (number or name)
The perfevent PMDA is not activated by default To install the PMDA,
do the following as root:
# cd $PCP_PMDAS_DIR/perfevent
If you want to undo the installation, do the following as root:
# cd $PCP_PMDAS_DIR/perfevent
pmdaperfevent is launched by pmcd(1) and should never be executed
directly. The Install and Remove scripts notify pmcd(1) when the
agent is installed or removed.
command line options used to launch pmdaperfevent$PCP_PMDAS_DIR/perfevent/perfevent.conf
default configuration file for the PMDA. See
perfevent.conf(5) for detailed information.
default help text file for the perfevent metrics
installation script for the pmdaperfevent agent
undo installation script for the pmdaperfevent agent
default log file for error messages and other information
Some metric names have changed starting in version 3.10.8 to better
conform to PMNS conventions. pmlogrewrite(1) can be used to update
old archives. A helper utility, $PCP_PMDAS_DIR/perfevent/perfevent-makerewrite.pl will generate a config file that is suitable for use
with pmlogrewrite(1) to update the metric names in existing archives.
Each event is placed in its own group and there is no way to group
related events together so they are guaranteed to be simultaneously
active. A workaround for this is to ensure that the number of
configured events is less than or equal to the number of available
hardware counters. This means that the events will not be time-
multiplexed by the kernel and will be simultaneously active.
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).
This page is part of the PCP (Performance Co-Pilot) project.
Information about the project can be found at ⟨http://www.pcp.io/⟩.
If you have a bug report for this manual page, send it to
firstname.lastname@example.org. This page was obtained from the project's upstream
Git repository ⟨git://git.pcp.io/pcp⟩ on 2017-03-13. If you discover
any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page, or
you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a mail
Performance Co-Pilot PCP PMDAPERFEVENT(1)