CA Allocate ASR Variable &FINVS can help prevent CA Disk space abends

Document ID : KB000039756
Last Modified Date : 14/02/2018
Show Technical Document Details


When CA Allocate attempts to select a volume from a Storage Group, if a volume
cannot be selected because of the size of the extent, the value of ASR variable
&FAILIFNOVOLSEL [alias &FINVS] is vital to prevent an abend.


Installations running both CA Disk and CA Allocate


The values specified with ASR variable &FINVS determines whether:
 - Y - CA Allocate fails the allocation immediately with: 'S99ERRCD = 04C8'.
   Message VAM0039 is issued describing the reason a volume was not selected.
For non-CA Disk allocations, 'Y' is a good setting because it insures that the
allocation will go only to the desired Storage Group, or it is failed.
 - N  (default) - CA Allocate does not immediately fail the allocation, but rather
   lets MVS DADSM retry the allocation using the original allocation attributes.
For non-CA Disk allocations, 'N' could allow the allocation to go to undesired
volumes or Storage Groups.



For CA Disk Restore or DMSAR allocations, &FINVS = 'N' is preferred because
the failure code 'S99ERRCD = 970C' will cause CA Disk to retry the allocation while
dynamically adjusting the allocation amount via CA Disk Sysparm PRIALLOC:
 - N  (default) - Consolidate space of all extents for allocation. 
 - 3 - Dynamically used if N fails, to consolidate the amount of the first 3 extents.
 - Y - Dynamically used if 3 fails, to use the original allocation amounts.
PRIALLOCN is the suggested value to specify (or let default).
NOTE: CA Disk PTF RO79961 is needed to fix a problem with PRIALLOC3
Here is the CA Allocate ASR logic that can be added in the ALLOC and DEFINE environments:
This statement will insure that:
 - &FINVS = 'Y' will be set for non-CA Disk allocations.
 - &FINVS = 'N' (default) will be used for CA Disk allocations.


Additional Information:

The "Reduce to Fit" ASR variables can be specified in ALLOC, DEFINE, EXTEND and EOV
environments to reduce large allocation amounts to help prevent SNA (Space Not Available) failures:
SET &RB = 10  [Allocation Reduced by this increment amount]
SET &MP = 50  [Allocation reduced only to this Minimum Percent of the original]
For very important information about the use of the DIF-RTF Variables,
please see Knowledge Document: TEC565055.
If any questions, please contact CA Technical Support.