PMDAMEMCACHE

Section: User Commands (1)
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NAME

pmdamemcache - memcached performance metrics domain agent (PMDA)

DESCRIPTION

This PMDA extracts performance data from memcached, a distributed memory caching daemon commonly used to improve web serving performance. A farm of memcached processes over multiple servers can be utilised by a single web application, increasing the total available object cache size, and decreasing the database load associated with smaller cache sizes. This system is described in detail at http://www.danga.com/memcached.

INSTALLATION

Configure pmdamemcache to extract the values from set of hosts used in the memcache farm. These hosts can be listed in the $PCP_PMDAS_DIR /memcache/memcache.conf file, in the format (i.e. Perl array) described at the top of pmdamemcache.pl. A custom refresh rate can also be configured using this mechanism.


# cd $PCP_PMDAS_DIR/memcache

# [ edit memcache.conf ]

Once this is setup, you can access the names and values for the memcache performance metrics by doing the following as root:


# cd $PCP_PMDAS_DIR/memcache

# ./Install

To uninstall, do the following as root:


# cd $PCP_PMDAS_DIR/memcache

# ./Remove

pmdamemcache 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

$PCP_PMDAS_DIR/memcache/memcache.conf
optional configuration file listing monitored memcache instances
$PCP_PMDAS_DIR/memcache/Install
installation script for the pmdamemcache agent
$PCP_PMDAS_DIR/memcache/Remove
undo installation script for the pmdamemcache agent
$PCP_LOG_DIR/pmcd/memcache.log
default log file for error messages from pmdamemcache

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

pmcd (1).


Index

NAME
DESCRIPTION
INSTALLATION
FILES
PCP ENVIRONMENT
SEE ALSO