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This section describes the JCL, data sets, and time coordination used with Tivoli Storage Manager.
Tivoli Storage Manager provides sample JCL in the ASAMPLIB data set that you can modify to help you prepare the server. The following members are available:
ASAMPLIB also contains other members that can help you complete other tasks after installation is complete. These members include:
A region size of 256MB (REGION=256M) is recommended for starting the Tivoli Storage Manager server. However, this value can be decreased or increased based on server workload. To determine the optimum value for your installation, monitor server operation and set the region size according to the results.
If the specified region is too small, server performance can be significantly impacted, especially during periods of high server activity. For example, the operating system GETMAIN and FREEMAIN processing can have a major impact on the performance of transaction-oriented applications such as Tivoli Storage Manager. To eliminate or minimize GETMAIN and FREEMAIN calls, the server uses its own method for satisfying storage requests. The ability of the server to avoid calls to the GETMAIN and FREEMAIN procedures is highly dependent on adequate region size for the workload.
When increasing the region size, use 128MB increments until the desired performance is achieved, or until it is clear that the additional storage is yielding improved performance. Once this occurs, you can reduce the region size in small increments (for example, 32 MB), to determine the optimum region size for your workload. It is important that performance be monitored for a period of time and over periods of high activity.
If the desired performance is not achieved after adjusting the region size, consult the Tivoli Storage Manager documentation and Redbooks for performance-related options and suggestions.
A region size of 0M (REGION=0M) is not recommeded. Specifying 0M will result in poor server performance.