General information

These worksheets address z/OS® Communications Server storage above 16MB; storage below 16MB is allocated as 150KB common storage, and 64KB private storage.

The heading "DISPLAY STATS ID" refers to the particular statistic identifier issued by the D NET,STATS command; this statistic identifier is used in the corresponding step of the worksheet. There are some statistics that D NET,STATS does not capture; they are indicated by N/A.

"Dynamic storage" refers to storage created in response to a need, and required only so long as the process using it stays active. Dynamic storage can be used to establish normal sessions, and for error recovery. Dynamic storage usage varies by configuration; it is related to the number of sessions being established. The worksheet yields an approximation of dynamic storage needed for a given configuration, assuming worst case system recovery.

Estimation of z/OS Communications Server storage is based on the following assumptions. (These assumptions reflect no implied or expressed recommendation.)

All PUs and LUs defined in the configuration are active.
Tables and user exit routines are not used.
Default buffer pool values, dynamic buffer expansion, and default start options are used.
Dynamic storage requirements are based on full system recovery.

In order to establish storage estimates, try the following steps:

Set REGION=0 for Private Storage, and CSALIMIT=0 for CSA/ECSA.
Monitor storage for approximately 2 or 3 weeks to determine what the peak values are.
When peak value is identified, then establish values for REGION and CSALIMIT. Use 1.5 times the peak value noted during the 2 or 3 week observation period.