Mainframe Capacity Planning: A Comprehensive Guide
Over the last half century, mainframes have proven their resilience. They handle billions of daily transactions for industries like banking, healthcare, and retail. But as workloads grow—driven by remote work, cloud integrations, and digital-first business models—the pressure on mainframes intensifies.
That’s why mainframe capacity planning has shifted from a “nice-to-have” to a business-critical strategy. Organizations that neglect it often face:
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Performance bottlenecks during peak business hours
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Unplanned downtime that disrupts customers and damages trust
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Escalating costs tied to inefficient MSU usage and suboptimal WLM settings
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Missed SLAs that directly impact revenue and compliance
By contrast, organizations that embrace structured capacity planning see measurable benefits:
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Optimized workload distribution across systems
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Reduced costs by smoothing peaks in 4-hour rolling averages
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Improved end-user experience thanks to consistent performance
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Greater agility to support new applications and users
This guide outlines the 8 essential steps for mainframe capacity planning—and shows how the zOptimization platform, zWorkload Reporter, and zGuard help you execute them effectively.
Eight Steps for Creating a Mainframe Capacity Planning Template
In this guide, we’ll explore the Mainframe capacity planning process, including how to create a capacity planning template and how to use it effectively with the help of the zOptimization platform.
Step 1: Identify Performance Metrics
The first step in the capacity planning process is to identify the key performance metrics that need to be monitored, including CPU utilization, memory usage, disk I/O, and network utilization. With zWorkload Reporter, you can easily monitor these metrics and get a clear picture of how your Mainframe system is performing, and identify areas where improvements can be made.
Step 2: Analyze Current Capacity
Once you’ve identified the performance metrics, it’s time to analyze the current capacity of your Mainframe system with zGuard. Without proper WLM management, your business may be vulnerable to unexpected moments of system overload, and you may only see limited benefits from WLM. By understanding how much capacity is currently being used and how much is available, you’ll be able to identify potential bottlenecks and plan for future growth.
Step 3: Forecast Future Growth
Based on business requirements and trends, forecast future growth of the Mainframe system. This could include factors like increasing workloads, new applications, and expanding user bases. zGuard empowers you to take better control of your Mainframe workloads. By understanding the expected growth of your Mainframe system, you’ll be able to plan for future capacity requirements.
Step 4: Plan for Capacity
Using the forecasting data, create a plan for future capacity requirements. This may involve WLM tuning, adding more CPUs, increasing memory, or expanding disk storage. With the zOptimization platform, you can plan for contingencies such as unexpected growth or temporary spikes in demand. By creating a comprehensive capacity plan, you’ll be able to ensure that your Mainframe system is able to handle the demands of your industry.
Step 5: Implement Capacity Plan
Once you’ve created a capacity plan, it’s time to implement it. This may involve adding new hardware, adjusting system settings, and configuring software. By implementing the zOptimization platform, you can test the new configuration to ensure that it is performing as expected. By carefully implementing the capacity plan, you’ll be able to avoid unexpected downtime and ensure optimal performance.
Step 6:Monitor Performance
Once the new configuration is in place, it’s important to monitor system performance daily with zWorkload Reporter to ensure that it is meeting expectations. By regularly monitoring performance, you’ll be able to identify potential issues and make adjustments as needed ahead of your peak periods.
Step 7: Adjust Capacity Plan
If performance issues are identified, zGuard can alert and adjust your Mainframe performance in real-time. This may involve making additional changes to hardware or software configuration, or adjusting system settings. You can be proactive in making adjustments, and avoid problems before they cause an issue.
Step 8: Report and Review
Finally, it’s important to report on capacity planning activities and system performance to stakeholders and review the process on a regular basis to ensure ongoing effectiveness. With the zWorkload Reporter and zGuard, you can keep stakeholders informed and regularly review the process to ensure that your Mainframe system is able to meet growing demands.
zOptimization Platform As Your Solution
Capacity planning is crucial for any organization that depends on a Mainframe system. By monitoring your environment with the zOptimization Platform, you can create a comprehensive capacity planning template and use it effectively to optimize performance and avoid unexpected downtime. With careful planning and ongoing monitoring, you can ensure that your Mainframe system meets your organization’s needs both now and in the future.
