ADR251W
xxx)-mmmmm(yy), ORPHAN FORMAT 3 AT DSCB C-H-R c-h-r

Explanation

This message is issued when DEFRAG processing detects an orphaned FORMAT 3 DSCB in the VTOC. Orphan FORMAT 3 DSCBs can occur if the DEFRAG process is interrupted while it is updating the VTOC and releasing FORMAT 3 DSCBs during data set extent consolidation. (A FORMAT 3 DSCB is converted to a FORMAT 0 DSCB.) An orphan FORMAT 3 indicates that either there is no FORMAT 1 DSCB that points to it, or that the orphan is in a chain of FORMAT 3 DSCBs and there is no FORMAT 1 DSCB that points to the chain.

System action

None.

Operator response

None.

Programmer response

Inspect the VTOC to ensure that the orphan FORMAT 3 does not represent a significant performance impact. If there are enough orphan FORMAT 3 DSCBs to make it difficult to obtain FORMAT 0 DSCBs for new allocations, do the following:
  • Perform a logical data set dump of all the data sets on the volume.
  • Reinitialize the volume.
  • Perform a logical restore of the dumped data sets.
  • Increase the size of the VTOC, if necessary.

Source

DFSMSdss

Parent topic: ADR message explanations