MAX DATA CACHING field (MXDTCACH subsystem parameter)
The MXDTCACH subsystem parameter specifies the maximum amount of memory, in MB, that is to be allocated for data caching for each thread.
| Acceptable values: | 0–512 |
|---|---|
| Default: | 20 |
| Update: | option 30 on panel DSNTIPB |
| DSNZPxxx: | DSN6SPRM MXDTCACH |
MXDTCACH controls memory allocation for queries that use sparse index access (PLAN_TABLE column PRIMARY_ACCESSTYPE='T') or pair-wise join access (PLAN_TABLE column JOIN_TYPE='P').
If you specify 0, Db2 does not use data caching during query execution. If you specify a value in the range 1–512, Db2 allocates memory from above the 2 GB bar pool up to the specified size for data caching.