Calculating CICS data space

Three tables are used to create CICS® data.

About this task

Collect CICS data as described below:
  1. Estimate the number of application programs that are used in the CICS region, using the CICS IA scanner. Call this number NUM_CICS_PROG.
  2. Estimate the average number of EXEC CICS calls per program, using the CICS IA scanner. Run the scanner against all load module data sets in the DFHRPL that make up your applications. There are three types:
    1. Key less than or equal to 32 bytes. Including all EXEC CICS calls other than those listed in step b. below. Call this number AVG_EXEC_SHORT.
    2. Resources greater than 32 characters. Currently only EXEC CICS ENQ or EXEC CICS DEQ have resource names greater than 32 bytes. Call this number AVG_EXEC_LONG.
    3. Resources that use DTP. These resources consist of the following commands: ALLOCATE, CONNECT, SEND, CONVERSE and FREE. Call this number AVG_DTP.
  3. Estimate the number of transaction and program associations. In this example, the estimate is that each can be associated with five transactions. Call this number PROG_TRAN_RATIO.
  4. Calculate CICS data space as follows:
     (108 * NUM_CICS_PROG * AVG_EXEC_SHORT  * PROG_TRAN_RATIO) + 
     (338 * NUM_CICS_PROG * AVG_EXEC_LONG  * PROG_TRAN_RATIO) + 
     ( 16 * NUM_CICS_PROG * AVG_DTP * PROG_TRAN_RATIO)  =   CICS_DS bytes.