Affinity tables and indexes
How to calculate the space required for the DB2® tablespace and DB2 indexes for Affinity data.
To calculate the space, in KB, to allocate for the DB2 tablespace and the DB2 indexes required for the Affinity collection,
estimate the total number of rows. In this example, there are three
tables:
- CIU_AFF_INDEX
- This table holds the group count for all the different affinity
types. The number of rows is fixed at 20.
NUM_ROWS = 20
- CIU_AFF_CMD_DATA
- The number of rows for this table is an estimate of the total
number of commands that cause affinities for each program in each
region. Calculate this number from the following values; see Table 1.
- NUM_AFF_PROG
- AVG_AFF
- NUM_REGION_D
The number of rows for the CICS® table can be calculated as follows:
NUM_ROWS = (NUM_AFF_PROG * AVG_AFF * NUM_REGION_D)
- CIU_AFF_GROUP_DATA
- The number of this table is an estimate of how many affinity groups
are required. Affinity commands stored in the CIU_AFF_CMD_DATA table
are grouped by affinity type, for example TSQueue type. Assume there
are four affinity commands per group.
Use the value calculated for NUM_ROWS and the values for ROW_SIZE and PERCENT_FREE in Table 1 to calculate the PRIQTY and SECQTY as described in DB2 space allocation for the Affinity tablespace.NUM_ROWS = (NUM_AFF_PROG * AVG_AFF * NUM_REGION_D) / 4
Tablespace | Row_Size | Percent_Free | PRIQTY | SECQTY |
---|---|---|---|---|
CIUAFFD | ||||
CIU_AFF_INDEX | 6 | 15 | ||
CIU_AFF_CMD_DATA | 61 | 15 | ||
CIU_AFF_GRP_DATA | 367 | 15 | ||
Indexes | ||||
X4AFFG11 | 10 | 20 | ||
X4AFFG12 | 81 | 20 | ||
X4AFFC11 | 57 | 20 | ||
X4AFFC12 | 53 | 20 | ||
X4AFFI11 | 6 | 20 | ||
X3GRPDAT | 255 | 20 | ||
X1GRPDAT | 10 | 20 | ||
X2AFFDAT | 22 | 20 | ||
X1AFFDAT | 42 | 20 |