Some types of recoverable resources, when they are accessed for update, cause logging. Do not define more resources as recoverable than you need for application programming requirements, because the extra logging incurs extra I/O and processor overheads. If the resource in question does not require recovery, these overheads are unproductive.
Specifying recovery increases processor time, real and virtual storage, and I/O requirements. It also increases task waits arising from enqueues on recoverable resources and system log I/O, and increases restart time.
Do not specify recovery if you do not need it. If the overhead is acceptable, logging can be useful for auditing, or if a data set has to be rebuilt.
For information on specific recoverable resources, see Tuning the use of CICS temporary storage (TS), and Optimizing the performance of the CICS transient data (TD) facility.
See the CICS® Recovery and Restart Guide for information on each resource to be specified as recoverable.
CICS auxiliary trace shows task wait time due to enqueues. RMF™ shows overall processor usage. CICS monitoring data shows task wait time due to journaling.