Tuning DEDB areas

Tuning DEDB areas mainly involves changing the DBD parameters and randomizers. When exceptionally large database records exist in the areas, additional preparation steps might be necessary.

Basic guidelines

The following basic guidelines generally apply when you tune areas in which exceptions are reported:
  • You should configure the DBD and the randomizing routine to optimize utilization of RAP CIs and to minimize the overflow to IOVF. Select an optimal CI size and optimal parameter values for the UOW and ROOT parameters at DBDGEN, and tune the randomizing routine so that the database record distribution can be optimized for the distribution of root key values and the distribution of database record lengths.
  • You should select database attributes to minimize the physical I/O requirements to meet the application performance criteria.