The Workload Management Advisor

WLM is code that runs on MVS mainframes. It can be queried to ask about the load on the MVS machine. When MVS Workload Management has been configured on your OS/390 system, Dispatcher can accept capacity information from WLM and use it in the load balancing process.

Using the WLM advisor, Dispatcher will periodically open connections through the WLM port on each server in the Dispatcher host table and accept the capacity integers returned. Because these integers represent the amount of capacity that is still available and Dispatcher expects values representing the loads on each machine, the capacity integers are inverted by the advisor and normalized into load values (that is, a large capacity integer but a small load value both represent a healthier server). The resulting loads are placed into the System column of the manager report.

There are several important differences between the WLM advisor and other Dispatcher advisors:
  • Other advisors open connections to the servers using the same port on which flows normal client traffic. The WLM advisor opens connections to the servers using a port different from normal traffic. The WLM agent on each server machine must be configured to listen on the same port on which the Dispatcher WLM Advisor is started. The default WLM port is 10007.
  • Other advisors only assess those servers defined in the Dispatcher cluster@port@server configuration for which the server’s port matches the advisor’s port. The WLM advisor advises upon every server in the Dispatcher configuration (regardless of the cluster@port). Therefore you must not define any non-WLM servers when using the WLM advisor.
  • Other advisors place their load information into the manager report under its “Port” column. The WLM advisor places its load information into the manager report under its system column.
  • It is possible to use both protocol-specific advisors along with the WLM advisor. The protocol-specific advisors will poll the servers on their normal traffic ports, and the WLM advisor will poll the system load using the WLM port.

Metric Server Restriction: Like the Metric Server agent, the WLM agent reports on server systems as a whole, rather than on individual protocol-specific server daemons. Metric Server and WLM place their results into the system column of the manager report. As a consequence, running both the WLM advisor and Metric Server at the same time is not supported.


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Timestamp icon Last updated: March 23, 2018 0:18
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