Geode 1.9 adopted Micrometer as a way to expose new metrics. Micrometer allows Geode developers measure internal details of Geode in a way that you can publish to a wide variety of external monitoring systems.
Each Geode cache has an internal "meter registry" that collects metrics about the cache and other aspects of the process in which it is running.
Geode's internal meter registry does not itself publish the metrics. It only collects them and makes them available for you to publish. If you want to publish Geode's metrics to an external monitoring system, you must add a "sub-registry" that knows how to publish to that monitoring system.
A "sub-registry" can be any implementation of Micrometer's MeterRegistry class. See the Micrometer documentation for descriptions of the available implementations, and instructions for how to configure them to send information to your monitoring system.
When you add a sub-registry to Geode, Geode adds all of its current meters to your sub-registry. It also adds any subsequently created meters and keeps your sub-registry informed of all future updates to the values of the meters.
Two Ways to Add a Meter Registry for Publishing
Geode offers two mechanisms to add a sub-registry for publishing. Which mechanism you choose depends on how you create the cache.
- If you create the cache using a
CacheFactory
, you can call the factory'saddSubregistry()
method one or more times to add sub-registries to the cache it creates. See Adding a Sub-Registry when Creating a Cache, below. - If the cache is created for you as part of a server or locator, you can implement a custom
MetricsPublishingService
service that initializes your sub-registry and adds it to the cache. See Adding a Sub-Registry to a Server or Locator below.
Adding a Sub-Registry when Creating a Cache
CacheFactory
provides a method which adds the given meter registry to the cache's composite registry for publishing cache metrics to external monitoring systems:
public CacheFactory addMeterSubregistry(MeterRegistry subregistry);
Example adding a meter sub-registry:
MeterRegistry prometheusRegistry = new PrometheusMeterRegistry(...); Cache cache = new CacheFactory() .addMeterSubregistry(prometheusRegistry) .create();
Example adding multiple meter sub-registries:
MeterRegistry prometheusRegistry = new PrometheusMeterRegistry(...); MeterRegistry influxRegistry = new InfluxMeterRegistry(...); MeterRegistry newRelicRegistry = new NewRelicMeterRegistry(...); Cache cache = new CacheFactory() .addMeterSubregistry(prometheusRegistry) .addMeterSubregistry(influxRegistry) .addMeterSubregistry(newRelicRegistry) .create();
Note: The above APIs are considered experimental. Micrometer metrics is a new addition to Geode 1.9 and the API may change.
Adding a Sub-Registry to a Server or Locator
The new interface org.apache.geode.metrics.MetricsPublishingService
provides an additional way to publish metrics generated by Micrometer meters in the cache meter registry. Geode discovers implementations of MetricsPublishingService
during cache creation, using the standard Java ServiceLoader
mechanism.
Example implementation of MetricsPublishingService
:
package com.application; public class MyMetricsPublishingService implements MetricsPublishingService { private volatile MeterRegistry registry; private volatile MetricsSession session; @Override public void start(MetricsSession session) { this.session = session; registry = ... // configure your meter registry and start publishing // add your registry as a sub-registry to the cache's composite registry session.addSubregistry(registry); } @Override public void stop() { ... // clean up any resources used by your meter registry ... session.removeSubregistry(registry); } }
To make your service available for loading, add the following provider-configuration file in the resource directory of your application Jar:
META-INF/services/org.apache.geode.metrics.MetricsPublishingService
Add a line inside the file indicating the fully qualified class name of your implementation:
com.application.MyMetricsPublishingService
Note: The above APIs are considered experimental. Micrometer metrics is a new addition to Geode 1.9 and the API may change.