Retained locks are created when a failure occurs. The locks need to remain until completion of the corresponding recovery. The retained locks only have meaning for RLS access. Lock requests issued by RLS access requests can encounter the retained locks. Non-RLS access does not perform record locking and therefore would not encounter the retained locks.

To ensure integrity of a recoverable data set, VSAM does not permit non-RLS update access to the data set while retained locks exist for that data set. There can be situations where an installation must execute some non-CICS applications that require non-RLS update access to the data set. VSAM RLS provides an IDCAMS command (SHCDS PERMITNONRLSUPDATE) that can be used to set the status of a data set to enable non-RLS update access to a recoverable data set while retained locks exist. This command does not release the retained locks. If this function is used, VSAM remembers its usage and informs the CICSs that hold the retained locks when they later open the data set with RLS.

If you use the SHCDS PERMITNONRLSUPDATE command, neither CICS nor DFSMStvs has any idea whether or not it is safe to proceed with pending backouts. Because of this, you must supply exits that DFSMStvs and CICS call, and each exit must tell the resource manager whether or not to go ahead with the backout. For more information, see the description of the batch override exit in IGW8PNRU Routine for Batch Override.