Refer to the performance and tuning documentation for your CICS server system for information on how to get the best performance.
Take care when extending a logical unit of work across multiple program link calls that might span a long time period (for example, user thinking time). The logical unit of work holds various locks, and other CICS resources, on the server. This might cause delays to other users who are waiting for the same locks and resources.
Also, each logical unit of work occupies one CICS non-facility task for the duration of its execution. This means that you must define enough free tasks in the CICS server to service the maximum expected number of concurrent calls.
Refer to CICS Transaction Gateway: Programming Guide for more information.