You might be experiencing various abends with Dispatch tasks (RPO, internal ARCHIVE, etc...) and/or at SHUTDOWN.
For the RPO and Archive tasks it may show up as being abends S878-10 which clearly identifies the problem as being a lack of virtual private area storage available to satisfy a storage request.
At shutdown it may manifest itself with messages like DC970063 V1 Bundle Control File Output Allocation Error shown in the Dispatch joblog.
More details of what the problem actually is can be found with the JESYSMSG JES2 sysout in the Dispatch task, like:
IKJ56893I DATA SET YOUR.CADS000.CNTL NOT ALLOCATED+
IGD306I UNEXPECTED ERROR DURING IEFSJRTE PROCESSING
RETURN CODE 8 REASON CODE 11014
THE MODULE THAT DETECTED THE ERROR IS IGDIDMSI
Reason code 11014 with message IGD306I is usually caused by a lack of below the line storage.
Such types of symptoms above (S878 abends, dynamic allocation failures, etc…) may have the same origin and is definitively related to a lack of storage below the line.
Common reason for this problem to occur is storage settings especially in relation with the REGION size allocated to the step that runs program CAISYS01 in the CADSDISP Dispatch JCL procedure.
Varying the value for the REGION size will affect the amount of STORAGE RETURNED TO OPSYS; in the example below REGION was set to 0M; the direct effect was a large amount of storage was showing up for the STORAGE RETURNED TO OPSYS:
DC390005 V1 RHDCPARM FREESTG RELEASED: 150K
DC390006 V1 REGION NEEDED TO START UP: 4,490K
DC390007 V1 SYSTEM CONFIGURATION SIZE: 4,340K
DC390008 V1 STORAGE RETURNED TO OPSYS: 6,574K
DC390020 V1 TOTAL AMOUNT OF XA STORAGE: 14,000K
A normal value for STORAGE RETURNED TO OPSYS should be slightly above 1000K, never below.
Default setting for this keyword in JCL procedure CADSDISP is REGION=7000K.
For local reason you may have to adjust the value, but always keep in mind the recommendation for STORAGE RETURNED TO OPSYS.
Setting REGION=0M with Dispatch definitively proved to cause problems.
See the CA Dispatch Systems Programmer Guide, Appendix A, Troubleshooting, Region Management for discussions about various problem related to storage.