JMX Management

The Java Management Extensions (JMX specification) describe an architecture, design patterns, API's, and services for application and network management in the Java programming language. JMX functions beyond a simple API since it can specify the architecture as to how that API is used. It provides the means to construct Java code, create smart Java agents, implement distributed management middleware and managers, and integrate these solutions smoothly into existing management systems. You can integrate such solutions with either HTML or industry standards such as SNMP and WBEM. JMX is dynamic, allowing the monitoring and management of resources in real time while they are created, installed, and implemented. The JMX also works along with JVM Java Virtual Machine. A virtual machine that enables a computer to run Java programs as well as programs written in other languages that are also compiled to Java bytecode., the Java Virtual Machine.

Manageable Resource

A JMX manageable resource can be an application, an implementation of a service, a device, a user, etc. It is developed in Java, or at least offers a Java wrapper, and must also be implemented by a Java object called a managed bean (MBeans), according to JMX specifications.

Opening JMX

Step 1. The easiest way to open JConsole for a specific service is through the GigaSpaces Management Center:

• In the Deployments tab, right-click the GSC Grid Service Container. This provides an isolated runtime for one (or more) processing unit (PU) instance and exposes its state to the GSM., GSM Grid Service Manager. This is is a service grid component that manages a set of Grid Service Containers (GSCs). A GSM has an API for deploying/undeploying Processing Units. When a GSM is instructed to deploy a Processing Unit, it finds an appropriate, available GSC and tells that GSC to run an instance of that Processing Unit. It then continuously monitors that Processing Unit instance to verify that it is alive, and that the SLA is not breached., or LookupService tree node, or

• In the Space Where GigaSpaces data is stored. It is the logical cache that holds data objects in memory and might also hold them in layered in tiering. Data is hosted from multiple SoRs, consolidated as a unified data model. Browser tab:

  • In the Grid Tree, right-click the relevant space container node, or

    

  • Right-click the relevant space node or clustered space node, or

    
    

  • Right-click the relevant space from the space network view:

    
    

Step 2. Click Launch JConsole.

Step 3. This opens the JConsole of the selected process.

Step 4. You can browse the various MBeans.

Step 5. Make sure you have a deployed space.

Step 6. Open a console and type the following command: jconsole

Step 7. Connect to the MBean server (choose one of the following options):

• Using the Advanced tab:

  1. The JConsole: Connect to Agent window appears. Select the Advanced tab.

  2. In the JMX URL text box, copy the URL in the log message displayed in your GigaSpaces Server,for example:

  3. Press Connect.

     

     New JMXConnectionServer was successfully registered into the MBeanServer using service url: service:jmx:rmi:///jndi/rmi://localhost:10098/jmxrmi.

• Using the Remote tab:

  1. The JConsole: Connect to Agent window appears. Select the Remote tab.

  2. In the Host or IP text box, copy the host name/IP address from JNDI URL text field in the container configuration.

  3. In the Port text box, copy the port value from the same JNDI URL text field in the container configuration.

     
     

     

Step 8. Press Connect.

Here is a code example of implementing such an approach:

IJSpace spaceProxy = ( IJSpace )SpaceFinder.find( "jini://mySpace_container/mySpace");
System.out.println( "Space found: " + spaceProxy.toString() );
ContainerConfig containerConfig = ( ( IJSpaceContainerAdmin )spaceProxy.getContainer() ).getConfig();
String jndiURL = containerConfig.jndiUrl;
Runtime.getRuntime().exec( "jconsole " + jndiURL );

Remote JConsole Connection

export GS_OPTIONS_EXT="-Dcom.sun.management.jmxremote.authenticate=true
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.access.file=[PATH_TO]/jmxremote.access
-Dcom.sun.management.jmxremote.password.file=[PATH_TO]/jmxremote.password"
export GS_JMX_REMOTE_BASE_PORT=[YOUR_PORT_VAL]

Viewing Thread CPU Usage

JConsole includes a plugin that displays CPU usage for each JVM thread. This tab is displayed using the -pluginpath JConsole parameter (already implemented in GigaSpaces).

To view this tab in your JConsole:

• Download the topthreads.jar file and add it to your $GS_HOME\lib\platform\ui folder.

  topthreads-1.0.0.jar is used by default. If topthreads-1.0.0.jar isn't found, the JTop.jar file (which is part of the JDK) is used instead.

The following subsections provide some sample screenshots.

topthread.jar

JTop.jar

MBeans View

The jconsole utility (part of Sun J2SE 5.0 JDK and above) includes a MBeans view, which allows you to perform space administration operations, and to view and control space attributes. These operations are defined in the JavaSpaceMBeanDescriptors.xml file, which exists in the xap-datagrid.jar file. If you do not want a certain operation or attribute to be exposed in the JMX MBeans tab, simply comment or remove the operation from the XML file.

Space Container MBean

The container MBean exposes the space container's attributes and operations. The space container manages the space life cycle.

Attributes Tab

The container Attributes tab displays a list of container attributes. Attribute values appearing in blue can be controlled, while values in black can not be changed. Red values are unavailable.

Operations Tab

The container Operations tab allows you to perform different space container operations:

Info Tab

The container Info tab displays the MBean name and its Java class.

Space MBean

The Space MBean exposes space attributes and operations. You can get the basic space operational settings using this MBean.

Attributes Tab

The space Attributes tab displays a list of space attributes/elements by XPath, in the selected space. Attribute values appearing in blue can be controlled, while values in black can not be changed. Red values are unavailable.

Operations Tab

The space Operations tab allows you to perform different space operations:

Info Tab

The space Info tab displays the MBean name and its Java class.

Space MBean Extension

The Space MBean Extension exposes advanced space attributes – this includes memory management, persistency and communication settings.

Attributes Tab

The space extensions Attributes tab displays a list of advanced space attributes/elements by XPath, in the selected space. Attribute values appearing in blue can be controlled, while values in black can not be changed. Red values are unavailable.

Info Tab

The space extensions Info tab displays the MBean name and its Java class.

Restricting and Modifying MBeans

There is an option to restrict the access to space and space container operations or attributes; for example, you can decide to hide some of the attributes and configuration, and disable execution of operations.

To do this, modify the following space and space container MBean Descriptors, which are located inside the $GS_HOME\lib\required\xap-datagrid.jar file:

• ContainerMBeanDescriptors.xml
• JavaSpaceExtMBeanDescriptors.xml
• JavaSpaceMBeanDescriptors.xml

Settings to Modify

Following are some space/space container MBeans Attributes settings you can modify:

• Attribute – required, otherwise is optional.
• name – the name of the attribute.
• type - The type or class name of the attribute.
• description – a description of the attribute.
• isReadable – true if the attribute has a getter method, false otherwise.
• isWritable – true if the attribute has a setter method, false otherwise.

Following are some space/space container MBeans Operations settings you can modify:

• Operation – required, otherwise optional.
• name – the name of the method.
• type – the type of the method's return value.
• impact – the impact of the method, one of INFO, ACTION, ACTION_INFO, UNKNOWN.
• description – a description of the operation.
• signature – MBeanParameterInfo objects describing the parameters (arguments) of the method.
• Signature – the list of parameters info.
  • Parameter – required, otherwise optional.
  • name – the name of the data.
  • type - the type or class name of the data.