1. Use space management techniques to set goals for efficient asset utilization:
• Higher asset utilization of storage hardware is essential for reducing energy consumption. Space management is an important SRM function that dramatically improves utilization. In fact, in large z/OS installations, an improvement in utilization of just a few percentage points can help recoup several terabytes in wasted disk space.
• Over time, smart space management policies can help an IT organization avoid the acquisition of multiple, additional disk subsystems. Utilizations in the 70 to 75 percent range are fairly typical. However, SRM can yield utilizations of 85 percent or more. This differential can significantly affect the size and timetable for infrastructure purchases.
Figure 1 shows the tracking of storage capacity on the floor against usage. The goal is to raise utilization to reduce costs and environmental impact. The “capacity (red) line increases, even though the usage (green) line doesn’t converge. This indicates storage acquisition is outstripping requirements.
Figure 2 shows another example of tracking business unit or application usage. Space allocated, but not used, is shown over time. Challenge data owners to improve efficiency and only request storage capacity that’s needed.
2. Accurate forecasting based on history and trending can prevent unnecessary purchases:
• No IT organization can afford to have empty drives spinning for no actual purpose. SRM helps eliminate this type of inefficiency by providing both detailed historical measurement functions and intelligent trending tools that enable accurate predictions of future space requirements. This helps organizations purchase storage configurations of the correct size and lets them continually update their forecasts to stay on top of changing conditions that might affect future storage needs.
• Space usage data can be collected for all storage groups, disk subsystems and/or applications to provide all stakeholders with the forecasting data they need. SRM technology should be centralized and made available to all appropriate IT staff. It may also be useful to make space management reports available on intranet sites or via email. This approach also ensures the entire storage environment isn’t repeatedly scanned by multiple users and departments, which can be a drain on CPU resources.