Enabling the serialization of ML2 data sets between RECYCLE and ABACKUP

The ABACKUP function locates data sets, including data sets on ML2 tapes, before backing them up. Before ABACKUP copies the data sets, RECYCLE processing may be invoked to process ML2 tapes. If ABACKUP tries to access data sets while RECYCLE is moving them from an ML2 tape, ABACKUP fails.

To prevent RECYCLE from moving a data set that ABACKUP is processing, issue the following PATCH command:

PATCH .MCVT.+195 BITS(......1.)

This patch turns ON a new bit, which causes RECYCLE to issue an enqueue request on the same resource that ABACKUP is processing. That is, RECYCLE issues an enqueue on the resource ARCDSN/dsname, where dsname is the name of the data set on ML2. Enqueue requests result in one of the following conditions:

If the enqueue fails, RECYCLE processing does not move the data set. If any data sets were skipped, a subsequent recycle of the volume will be necessary to move them.
If the enqueue succeeds, RECYCLE de-serializes the resource after the data set is moved.

Note: Because these enqueues may negatively impact RECYCLE performance, they are performed only if you issue the PATCH command for any DFSMShsm on which RECYCLE runs.