Consider the mix of workloads that run on mainframes. Sure, there are monitoring tools, but where’s the problem? How do you pin down the issue? DASD is one of the few mechanical devices left in the data center, but it doesn’t take much for DASD issues to drastically affect system performance. Conversely, adding cache memory to avoid I/O wait can improve performance.
Unfortunately, solving storage-related performance issues is rarely as simple as adding cache to an array. The symptoms are usually non-specific workload slowdowns, so merely identifying the issue can be a struggle. Through reporting and automation capabilities, storage administrators can monitor the storage configuration for warning signs of impending problems from various sources:
- System Managed Storage (SMS)
- Hierarchical Storage Management (HSM)
- Storage devices
- Other resources.
Ideally, the storage administrator has a tool that consolidates disparate information into one, easy-to-use application, eliminating the problem of selecting one of the many available tools.
A storage administrator’s job frequently includes interactions with performance analysts. About 20 percent of a storage administrator’s time is spent worrying about performance-related issues. Of that percentage, the vast proportion is spent concerning transaction processing and databases. Tools can help with this process by providing the ability to drill down from user data sets—through emulated mainframe volumes to vendor disk subsystems—to diagnose and correct performance and availability issues. The storage administrator must have a clear view of what’s happening from a performance standpoint and be able to communicate with performance analysts who have access to baseline data.