Recommendation for Fast Path transactions in a shared-queues environment

For shared Fast Path transactions, if you specify LOCALONLY in the Fast Path Input Edit/Routing exit routine (DBFHAGU0), do not change the size of your EMH buffer pools. The same buffer pool space is required for a shared-queues environment as for a non-shared-queues environment.

However, if you specify LOCALFIRST in DBFHAGU0 for shared Fast Path transactions and the transaction is processed locally, both a front-end EMH buffer and a back-end EMH buffer are required in the local IMS system; consequently the EMH buffer pool usage increases.

In either case, analyze EMH buffer usage and adjust the space as needed.

Related reading: For more information on tuning for performance in a shared-queues environment, see Planning for performance in a shared-queues environment.