4-Hour Rolling Average

The 4-hour rolling average plays a significant role in determining your mainframe operating costs. It’s just a metric, but a crucially important one. IBM uses it to determine your company’s software monthly license charges. So, when you find a way to lower your 4-hour rolling average (4HRA) you can help your IT department directly save money.

This sounds simple enough, but improving this metric without reducing your workload capacity is easier said than done. However, once you take the time to understand how the 4-hour rolling average works, how it’s calculated, and how it can save money, being 4HRA sensitive can revolutionize your company’s monthly software expenses.

How Software Pricing Works

Generally, software monthly license charge (MLC) is priced based on peak MSU (millions of service units) usage per month, not on actual machine capacity. To provide a fair pricing model, IBM supports the use of sub-capacity licensing and bases its price on the 4-hour rolling average of your mainframe’s MSU consumption. Basically, the tech giant looks at the average MSU used for all 4-hour periods within a month and uses the peak 4HRA to determine your monthly license charges. Where you may be losing out, is if your peak utilization per hour is particularly high during some hours due to running jobs while your mainframe is heavily used for high priority workloads.

IBM allows you to implement soft capping. This technique allows you to set a capacity limit for your system. Then, you are charged based on whatever is lower, your peak 4HRA or your defined capacity. Soft capping combined with active capacity management can lead to significant IT cost reduction.

Managing Your Resources

While workload does impact the 4-hour rolling average, how a system is tuned will also contribute to this metric. The quality of your code, system parameters, and data structures will all impact the 4HRA.

When a developer goes in and looks at what are the quiet hours for the LPARs – the logical partition of your mainframe into sets of resources – it is then possible to fine-tune your workloads to run during these times. Code should be written so the jobs, which can be moved, will run during these lean periods, not during peak processing hours. It’s also possible to make improvements by streamlining these workloads.

This will force your mainframe to consume only MSUs that are essential for the necessary workloads, rather than overconsuming in some periods. Even something as simple as moving a job by half an hour can reduce the peak 4HRA.

Getting the Right Insights for Accurate Tuning

It’s essential to adjust the right workloads to reduce costs. Modeling technology can be used to get a clear picture into your mainframe’s resource consumption and how it changes over time. Your IT team can get the necessary insight to identify the best options for tuning your workloads.

Lowering your software MLC bill can make a dramatic difference to your company’s bottom line. By simply tuning your workloads and actively managing your MSU consumption, it is possible to see a significant expense reduction.

Ready to learn about other options to lower your company’s 4-hour rolling average and see how much you can save? We’ll introduce you to a unique technology innovation that helps lower your 4HRA. Contact us today: https://alebra.com/contact/

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