EJB Work Load Management with Java/J2EE clients

Technote (FAQ)
Problem
A description of EJB™ Work Load Management (WLM) with Java™/J2EE™ clients for V3.5, V4.0, and V5.0 releases of WebSphere® Application Server.
Solution
For all releases of WebSphere Application Server V3.5 Advanced Edition - Java Client

To use the EJB WLM feature you must first WLM-enable your Java™ Archive (JAR) files.

Enabling WLM on the Client JAR (deployed JAR)

You can do this from the $WAS_HOME directory command prompt using the wlmjar.cmd (Windows®) and the wlmjar.sh (Unix®).

Syntax:

wlmjar-J jar_file -P package-IF remote_interface
[-M ]
[-V ]

Usage:
wlmjar <options>

Options:
-J jar file (required)
-IF remote interface
( bean or beanHome (at least one required)
-P package (required)
-M (optional: reuse manifest)
-V verbose mode

Specify the beans (and their homes) that you want to WLM enable.

For example, to WLM-enable the BeenThere bean sample .jar file:

$WAS_HOME/bin/wlmjar.cmd -J BeenThere.jar -IF BeenThere -IF BeenThereHome -P com.ibm.websphere
Result:
The wlmjar command will prepend _wlm_ to the resulting jar file to show that it was WLM-enabled. If the .jar file already has _wlm_ prepended, you can rename the jar file.

Additional Information:

WebSphere Scalability: WLM and Clustering - IBM Redbook
  • Appendix B. WLM enabling EJBs
  • Appendix C. WLM tuning properties

WebSphere Application Server V3.5 AE Information Center
  • 7: Multimachine management
  • 7.2 Managing workloads
  • 7.2.8 Workload management for stand-alone Java clients
  • 7.2.5 Using workload management - a sample procedure
  • 8.4.1.3: Workload Management/Cloning/Remote Administration Problems

For all releases of WebSphere Application Server V4.0

To enable WLM for Java/J2EE clients, perform either a WebSphere Client installation or a WebSphere Application Server installation on the client side.
    FAQs
    1. What is a J2EE client? How does a client program qualify as a J2EE client?
      • A client that runs using the launchClient utility that is provided with WebSphere Application Server and located in the $WAS_HOME>/bin directory
      • A servlet or JSP
      • A Java client that is run outside of the launchClient utility, meaning the client container and like objects are not available to the client. Ensure that the wlm.jar is in the classpath.
    2. What is a client installation?

      There is a separate client installation CD available for this purpose. This is not the same as a client program, such as the remote console, wscp, or xmlconfig.
    3. How do I get the Client CD code?

      Log onto Passport Advantage to download the image for
      WebSphere Application Server V4.0 Advanced Client Install
      (C40B2ML.exe)

IMPORTANT:

It is strongly recommended that you install WebSphere Application Client or WebSphere Application Server on your client machine.

Some customers copy the jars from a WebSphere Application Server system to the client system and try to use WLM-enabled clients, reviewing the setupcmdline.bat/sh file in the $WAS_HOME\bin directory and using that file as a reference to set up the client classpath environment.

This is not recommended or supported. The support team will do their best to fix the problem. To have proper WLM, there must be more then just the WLM jars in the classpath.

With this setup you might not get the client side WLM traces. It is also difficult to debug any errors. The client is the one making calls to different EJB servers and you must have the client traces.

For Additional Information:
WebSphere Application Server V4.0 AE Information Center
  • Chapter 4.7 Java Clients
  • Chapter 7.2.8 Workload management for stand-alone Java clients

IBM WebSphere V4.0 Advanced Edition Handbook - IBM Redbook
  • Chapter 17.5.9 WLM for Java clients


For all releases of WebSphere Application Server V5.0 - Clients

To enable WLM for Java/J2EE clients, you must perform either a WebSphere Client installation or a WebSphere Application Server installation on the client side.

Using application clients:
Application client functions:
Use the following links to identify the available functions in the different types of clients
launchClient tool:
Running WebSphere Application Server across versions

WebSphere Application Server V5.0 is generally interoperable with all releases of WebSphere Application Server V3.5 and V4.0; however, there are specific requirements to address for each version. Make the following changes to support interoperability between versions:
Additional Information:











Document Information

Product categories: Software, Application Servers, Distributed Application & Web Servers, WebSphere Application Server, Workload Management (WLM)
Operating system(s): AIX, HPUX, Linux, Multi-Platform, Solaris, Windows
Software version: 3.5, 4.0, 5.0
Software edition: Advanced, Base, Network Deployment
Reference #: 1165697
IBM Group: Software Group
Modified date: 2004-07-27