very 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
                _[platform].log_ is written in the current directory of
                [pmcd(1)](../man1/pmcd.1.html) when **pmda[platform]** 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
                either the privileged "root" account on some platforms
                (Linux, for example) or the unprivileged "pcp" account
                (wherever possible).
    

##  INSTALLATION  top

    
    
           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  top

    
    
           **$PCP_PMDAS_DIR/[platform]/help**
                  default help text file for the the kernel metrics
           **$PCP_LOG_DIR/pmcd/[platform].log**
                  default log file for error messages and other information
                  from the kernel PMDA.
    

##  PCP ENVIRONMENT  top

    
    
           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)](../man5/pcp.conf.5.html).
    

##  SEE ALSO  top

    
    
           [PCPIntro(1)](../man1/PCPIntro.1.html), [dbpmda(1)](../man1/dbpmda.1.html), [pmcd(1)](../man1/pmcd.1.html), [pcp.conf(5)](../man5/pcp.conf.5.html) and [pcp.env(5)](../man5/pcp.env.5.html).
    

##  COLOPHON  top

    
    
           This page is part of the _PCP_ (Performance Co-Pilot) project.
           Information about the project can be found at 
           â¨<http://www.pcp.io/>â©.  If you have a bug report for this manual
           page, send it to pcp@groups.io.  This page was obtained from the
           project's upstream Git repository
           â¨<https://github.com/performancecopilot/pcp.git>â© on 2023-12-22.
           (At that time, the date of the most recent commit that was found
           in the repository was 2023-12-16.)  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 to
           man-pages@man7.org
    
    Performance Co-Pilot               PCP                   _KERNEL_PMDAS_(1)
    

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