After upgrade to z/OS 2.4 from z/OS 2.2, Disk jobs are abending with S878-10 abends . After increasing the REGION sizes to 0M the jobs still abend with S878-10.
Release : 14.0
The issue was caused by the enablement of the RUCSA after the z/OS 2.4 upgrade. 10M was specified for below the line storage. RUCSA enablement takes up 3M of it. IBM mentioned specifying 0M would only be allowing 6M for storage.
As a work around splitting the jobs apart and not backing up so many volumes at once would help.