IMS® tables and index: CIUIMS

Calculation of the space required for the Db2® tablespace and Db2® index for IMS® data.

To calculate the space, in KB, to allocate for the Db2® tablespace and the Db2® index required for IMS® data, you need to estimate the total number of rows.

Calculate this number from the following values; see Values required for each CICS® region.
  • NUM_IMS_PROG
  • AVG_IMS
  • PROG_TRAN_RATIO
  • NUM_REGION_D
Calculate the number of rows for the Db2® table as follows:
NUM_ROWS = (NUM_IMS_PROG * AVG_IMS * 
            PROG_TRAN_RATIO * NUM_REGION_D) 

Use the value calculated for NUM_ROWS and the values for ROW_SIZE and PERCENT_FREE in Worksheet for IMS tablespace to calculate the PRIQTY and SECQTY as described in Db2 space allocation for the IMS® tablespace.

Table 1. Worksheet for IMS® tablespace
Tablespace Row_Size Percent_Free PRIQTY SECQTY
CIUIMSD 127 15
Indexes
XIIMSD1 69 20