Planning considerations for the RECON data sets

Define your RECON data sets specifying VSAM SHAREOPTION(3,3). Each data set should be on a different volume and catalog. The RECON data sets should also be of different sizes.

Each RECON data set is a VSAM KSDS with a 32-byte key.

Recommendations:
  • When defining the RECON data sets using Access Method Services (AMS):
    • Use the same index control interval (CI) size and data CI size for all the RECON data sets.
  • Ensure that the data CI size specified exceeds the specified index CI size by at least 2048 bytes. Failure to do so can seriously degrade your DBRC performance.
  • Use secondary allocation to safeguard against a RECON data set becoming full.