One of the strengths of the zSeries platform and the z/OS operating system is the ability to run multiple workloads at the same time within one z/OS image or across multiple images. Such workloads have different, often competing completion and resource requirements. These requirements must be balanced in order to make the best use of the resources of an installation, maintain the highest possible throughput and achieve the best possible system responsiveness. The function that makes this possible is dynamic workload management, which is implemented in the Workload Management component of the z/OS operating system.
With z/OS Workload Management (WLM), you define performance goals and assign a business importance to each goal. You define the goals for work in business terms, and the system decides how much resource, such as CPU or storage, should be given to it to meet the goal. Workload Management will constantly monitor the system and adapt processing to meet the goals.
The IBM Redbook, System Programmer's Guide to: Workload Manager, gives a broad understanding of the Workload Management component of the z/OS system. It covers basic aspects of WLM, and provides a discussion on how to create WLM policies based on business goals and the types of transactions you run in your systems.
This book also provides information on how to implement the WLM functions, in addition to suggestions on how to classify the different workloads to WLM so that it can best manage the different types of units of work. You will find information for effective performance analysis and a description of how to use the WLM functions to achieve a better throughput in your environment. This book also provides some best practice samples to better understand how to set up your classification and tune it.
The Workload Management task in the z/OS Management Facility (z/OSMF) provides a browser-based user interface that you can use to manage WLM service definitions and provide guidelines for WLM to use when allocating resources. Specifically, you can define, modify, view, copy, import, export, and print WLM service definitions. You can also install a service definition into the WLM couple data set for the sysplex, activate a service policy, and view the status of WLM on each system in the sysplex. This simplifies management of WLM and reduces the level of expertise needed.