pmdalio(1) — Linux manual page


PMDALIO(1)               General Commands Manual              PMDALIO(1)

NAME         top

       pmdalio - Linux LIO subsystem PMDA

DESCRIPTION         top

       pmdalio is a Performance Metrics Domain Agent (PMDA) which
       exports metric values about the Linux I/O target subsystem, which
       provides for protocols like iSCSI, FCP, FCoE.  These allow
       storage available on one host to be exported and consumed by
       other hosts using industry standard protocols.

       This PMDA exports summary metrics which are performance value
       aggregations and configuration per LIO target instance.
       Additionally, it provides per LUN performance metrics including
       IOPS, and READ and WRITE throughput.

       The LIO configuration is maintained within the kernel's configfs
       virtual filesystem.  The python-rtslib module provides an
       interface to configfs, allowing tools like pmdalio to interact
       with the settings and metadata held in configfs.

INSTALLATION         top

       Install the lio PMDA by using the Install script as root:

           # cd $PCP_PMDAS_DIR/lio
           # ./Install

       To uninstall, do the following as root:

           # cd $PCP_PMDAS_DIR/lio
           # ./Remove

       pmdalio 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.

FILES         top

           installation script for the pmdalio agent

           undo installation script for the pmdalio agent

           default log file for error messages from pmdalio


       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

SEE ALSO         top

       PCPIntro(1), pmcd(1), pminfo(1) and pmpython(1).

COLOPHON         top

       This page is part of the PCP (Performance Co-Pilot) project.
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       ⟨⟩ on 2023-12-22.
       (At that time, the date of the most recent commit that was found
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Performance Co-Pilot               PCP                        PMDALIO(1)