Temporary Storage

The costing for temporary storage covers the following:

In each example, n represents the number of items in the queue before it is deleted.

Main Storage

WRITEQ REWRITE READQ DELETEQ
1.0 0.8 0.8 0.71 + 0.23 * n

Auxiliary Storage

The approximations for auxiliary TS queues do not include any VSAM I/O cost. A VSAM I/O costs approximately 11.5K instructions and will occur as follows:

Therefore, under certain circumstances, a READQ could incur the cost of two VSAM I/Os.

Non-Recoverable TS Queue

WRITEQ REWRITE READQ DELETEQ
1.3 1.8 1.0 0.75 + 0.18 * n

Recoverable TS Queue

WRITEQ REWRITE READQ DELETEQ
1.4 19 1.0 0.87 + 0.18 * n
Note:
The main difference between the cost of accessing non-recoverable and recoverable TS queues is incurred at syncpoint time, when, for recoverable queues, the following happens:

Shared Temporary Storage

For information about performance measurements on shared temporary storage, see the System/390® MVS™ Parallel Sysplex® Performance manual.

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