Performance considerations
Subzero might extend the overall response time for subsystem access requests; transferring a subsystem access request through XCF to remote LPARs naturally takes longer than accessing subsystems with local, cross-memory techniques.
Therefore, you should consider the potential performance effects of redirection in the following areas:
Locking
Database locks might be held longer while waiting for a single transaction to complete all of its database interaction and commit any updates.
Transaction queuing
Transaction residency might be higher due to the elongated subsystem access, and transaction queues can become deeper. More client address spaces might be required to provide better transaction balancing and throughput.
Performance monitoring
Subzero is transparent to the client (such as applications that run under CICS) and the target (remote) subsystem. In a monitoring product, the client and target subsystems reflect connectivity to each other. However, for hyperlinks to work between the client and subsystem monitors, the monitors must recognize that the hyperlink target is running on a remote LPAR. Attempting to connect the monitor to a Subzero server causes errors: the control block structures that the monitor analyzes do not recognize the Subzero internal control blocks.
MainView products provide maintenance to recognize and support a Subzero environment.
Tuning efforts can mitigate performance issues. For more information, see Tuning-your-environment-for-Subzero.