Preparing for Installation › Storage Requirements › ECSA Usage and Storage Requirements

ECSA Usage and Storage Requirements

CA OPS/MVS uses a minimal amount of below-the-line CSA storage; at most, the main CA OPS/MVS address space uses about 2 KB of storage below the 16-MB line. CA OPS/MVS achieves this low CSA usage by using z/OS cross-memory services extensively, so the extended private area of the main CA OPS/MVS address space can store globally used data areas. However, much of the CA OPS/MVS code and some data areas reside in extended CSA (ECSA) storage.

We strongly recommend that you reserve 500 KB of ECSA for the use of CA OPS/MVS. Most sites have so much ECSA allocated that earmarking 500 KB for CA OPS/MVS does not require you to increase the amount of ECSA. However, if your site runs with a limited amount of ECSA, increase it by 500 KB before you install CA OPS/MVS.

Notes:

• The bottom of ECSA is rounded to a 1 MB boundary, so you may have more ECSA than you think.
• If CA OPS/MVS terminates abnormally, there may not be enough ECSA to load all necessary modules and restart CA OPS/MVS. Should this occur, IPL your system to free an appropriate amount of common storage. If you think that this could happen at your data center, ensure that the second value of your IEASYSxx CSA parameter is sufficiently large (for example, CSA=(x,40000)). If you use the CA OPS/MVS module reload facility to reload ECSA resident modules, you will find that ECSA usage of CA OPS/MVS increases. Replaced modules are not deleted until product shutdown.