Chapter 23. Set Up Java Management Extensions (JMX)

23.1. About Java Management Extensions (JMX)

Java Management Extension (JMX) is a Java based technology that provides tools to manage and monitor applications, devices, system objects, and service oriented networks. Each of these objects is managed, and monitored by MBeans.

JMX is the de facto standard for middleware management and administration. As a result, JMX is used in Red Hat JBoss Data Grid to expose management and statistical information.

23.2. Using JMX with Red Hat JBoss Data Grid

Management in Red Hat JBoss Data Grid instances aims to expose as much relevant statistical information as possible. This information allows administrators to view the state of each instance. While a single installation can comprise of tens or hundreds of such instances, it is essential to expose and present the statistical information for each of them in a clear and concise manner.

In JBoss Data Grid, JMX is used in conjunction with JBoss Operations Network (JON) to expose this information and present it in an orderly and relevant manner to the administrator.

23.3. JMX Statistic Levels

JMX statistics can be enabled at two levels:

  • At the cache level, where management information is generated by individual cache instances.
  • At the CacheManager level, where the CacheManager is the entity that governs all cache instances created from it. As a result, the management information is generated for all these cache instances instead of individual caches.
Important

In Red Hat JBoss Data Grid, statistics are enabled by default in Remote Client-Server mode and disabled by default for Library mode. While statistics are useful in assessing the status of JBoss Data Grid, they adversely affect performance and must be disabled if they are not required.

23.4. Enabling JMX for Cache Instances

You can enable JMX statistics at the Cache level either declaratively or programmatically.

Declaratively Enabling JMX at the Cache Level

Add the statistics attribute to the target <*-cache> element as follows:

<*-cache statistics="true">

Programmatically Enabling JMX at the Cache Level

Programmatically enable JMX at the cache level as follows:

Configuration configuration = new
ConfigurationBuilder().jmxStatistics().enable().build();

23.5. Enabling JMX for CacheManagers

You can enable JMX statistics at the CacheManager level either declaratively or programmatically.

Declaratively Enabling JMX at the CacheManager Level

Add the statistics attribute to the <cache-container> element as follows:

<cache-container statistics="true">

Programmatically Enabling JMX at the CacheManager Level

Programmatically enable JMX at the CacheManager level as follows:

GlobalConfiguration globalConfiguration = new
GlobalConfigurationBuilder().globalJmxStatistics().enable().build();

23.6. Disabling the CacheStore via JMX When Using Rolling Upgrades

Red Hat JBoss Data Grid allows the CacheStore to be disabled via JMX by invoking the disconnectSource operation on the RollingUpgradeManager MBean.

See Also: RollingUpgradeManager

23.7. Multiple JMX Domains

Multiple JMX domains are used when multiple CacheManager instances exist on a single virtual machine, or if the names of cache instances in different CacheManagers clash.

To resolve this issue, name each CacheManager in manner that allows it to be easily identified and used by monitoring tools such as JMX and JBoss Operations Network.

Set a CacheManager Name Declaratively

Add the following snippet to the relevant CacheManager configuration:

<globalJmxStatistics enabled="true" cacheManagerName="Hibernate2LC"/>

23.8. MBeans

23.8.1. MBeans

An MBean represents a manageable resource such as a service, component, device or an application.

Red Hat JBoss Data Grid provides MBeans that monitor and manage multiple aspects. For example, MBeans that provide statistics on the transport layer are provided. If a JBoss Data Grid server is configured with JMX statistics, an MBean that provides information such as the hostname, port, bytes read, bytes written and the number of worker threads exists at the following location:

jboss.infinispan:type=Server,name=<Memcached|Hotrod>,component=Transport

MBeans are available under two JMX domains:

  • jboss.as - these MBeans are created by the server subsystem.
  • jboss.infinispan - these MBeans are symmetric to those created by embedded mode.

Only the MBeans under jboss.infinispan should be used for Red Hat JBoss Data Grid, as the ones under jboss.as are for Red Hat JBoss Enterprise Application Platform.

Note

A full list of available MBeans, their supported operations and attributes, is available in the Appendix

23.8.2. Understanding MBeans

When JMX reporting is enabled at either the Cache Manager or Cache level, use a standard JMX GUI such as JConsole or VisualVM to connect to a Java Virtual Machine running Red Hat JBoss Data Grid. When connected, the following MBeans are available:

  • If Cache Manager-level JMX statistics are enabled, an MBean named jboss.infinispan:type=CacheManager,name="DefaultCacheManager" exists, with properties specified by the Cache Manager MBean.
  • If the cache-level JMX statistics are enabled, multiple MBeans display depending on the configuration in use. For example, if a write behind cache store is configured, an MBean that exposes properties that belong to the cache store component is displayed. All cache-level MBeans use the same format:

    jboss.infinispan:type=Cache,name="<name-of-cache>(<cache-mode>)",manager="<name-of-cache-manager>",component=<component-name>

    In this format:

    • Specify the default name for the cache using the cache-container element’s default-cache attribute.
    • The cache-mode is replaced by the cache mode of the cache. The lower case version of the possible enumeration values represents the cache mode.
    • The component-name is replaced by one of the JMX component names from the JMX reference documentation.

As an example, the cache store JMX component MBean for a default cache configured for synchronous distribution would be named as follows:

jboss.infinispan:type=Cache,name="default(dist_sync)", manager="default",component=CacheStore

Each cache and cache manager name is within quotation marks to prevent the use of unsupported characters in these user-defined names.

23.8.3. Registering MBeans in Non-Default MBean Servers

The default location where all the MBeans used are registered is the standard JVM MBeanServer platform. Users can set up an alternative MBeanServer instance as well. Implement the MBeanServerLookup interface to ensure that the getMBeanServer() method returns the desired (non default) MBeanServer.

To set up a non default location to register your MBeans, create the implementation and then configure Red Hat JBoss Data Grid with the fully qualified name of the class. An example is as follows:

To Add the Fully Qualified Domain Name Declaratively

Add the following snippet:

<globalJmxStatistics enabled="true" mBeanServerLookup="com.acme.MyMBeanServerLookup"/>