Memcached plugin

Memcached is an in-memory key-value store for small chunks of arbitrary data (strings, objects) from results of database calls, API calls, or page rendering. For more information visit memcached.org.

Discovery

Even if the memcached plugin is not configured, Monitoring will discover memcached services running in your Cloud Platform project by:

• searching instance names for memcached
• checking for ports opened to 11211 via firewall rules

The services discovered are displayed on the memcached Services page in the Resources menu. After you install the monitoring agent and configure the memcached plugin on your instances, Monitoring populates the memcached Services page with inventory and metrics.

Configuring Monitoring to monitor memcached

After you install the monitoring agent, use the following instructions to configure the memcached plugin on your instances.

Enabling the memcached monitoring plugin

On your VM instance, download memcached.conf from the GitHub configuration repository and place it in the directory /opt/stackdriver/collectd/etc/collectd.d/:

(cd /opt/stackdriver/collectd/etc/collectd.d/ && curl -O https://raw.githubusercontent.com/Stackdriver/stackdriver-agent-service-configs/master/etc/collectd.d/memcached.conf)

After adding the configuration file, restart the monitoring agent by running the following command:

sudo service stackdriver-agent restart

Information on other plugin configuration options can be found at collectd.org.

What is monitored

The Memcached plugin monitors the following metrics:

• Connections (count): The number of connections currently attached to memcached.
• Hit Ratio (percent): The ratio of cache hits to misses.
• Item Count (count): The number of keys currently being cached.

For details, see Agent metrics list: memcached.