PDSE resource contention in a multi-tasking TSO BATCH environment

This is a former DCR MR0923135057 issued on 23th September 2013 and public RFE of private RFE 47867. According IBM this is already in implementation of next z/OS release.

Under the existing z/OS architecture accessing a PDSE resource in a
multi-tasking TSO BATCH environment can result in PDSE resource
contention issues when a authorized command or program is executed from
within the multi-tasking batch TSO job.

The scheduling of an authorized command or program in a multi-tasking
TSO batch environment will STATUS STOP all currently executing
unauthorized work. The PDSE serialization issue will occur when the
dispatchable authorized command or task needs a PDSE resource that is
held by another task that is STATUS STOPped.

TSO authorized command processing doesn't have a means to check for
currently active cross memory requests and PDSE is not architectured
with any means to indicate that a particular TCB has an active cross
memory PDSE request.

This issue is not unique to PDSE as any non authorized cross memory
processing, that obtains serialization while executing in a
multi-tasking BATCH TSO environment is exposed.

TSO authorized command processing needs to be enhanced so that this type
of code contention does not occur.