CQMINTV - Empty intervals listing causes slowness

CQMINTV command struggles when it lists too many empty intervals(AVAIL NO). Our DBAs were quite unhappy when they figured out the issue. The problem was when the backstore datasets are removed/deleted from the disc and when CQMINTV list those as empty intervals the response time lasts up to 10mins for the output of CQMINTV to be retrieved for a four way data sharing systems.

Should one expect Query monitor to list the empty intervals as it's quite understandable when they are not available in the disc. If they are still needed to be highlighted then wouldn't it be nice to have some control in CQMPARMS to decide how many empty intervals that CQMINTV can list at the maximum. Below is the sample of how the output from CQMINTV look like specially when it lists the empty intervals.

CMD AVAIL START END

-- ------ --------------------- ---------------------

__ MIGRAT 02/16/2023 - 0:00:00 02/16/2023 - 2:00:00

__ NO 02/15/2023 - 22:00:00 02/16/2023 - 0:00:00

__ NO 02/15/2023 - 20:00:00 02/15/2023 - 22:00:00

__ NO 02/15/2023 - 18:00:00 02/15/2023 - 20:00:00

__ NO 02/15/2023 - 16:00:00 02/15/2023 - 18:00:00

__ NO 02/15/2023 - 14:00:00 02/15/2023 - 16:00:00

__ NO 02/15/2023 - 12:00:00 02/15/2023 - 14:00:00

__ NO 02/15/2023 - 10:00:00 02/15/2023 - 12:00:00

__ NO 02/15/2023 - 8:00:00 02/15/2023 - 10:00:00

__ NO 02/15/2023 - 6:00:00 02/15/2023 - 8:00:00

__ NO 02/15/2023 - 4:00:00 02/15/2023 - 6:00:00

__ NO 02/15/2023 - 2:00:00 02/15/2023 - 4:00:00

__ NO 02/15/2023 - 0:00:00 02/15/2023 - 2:00:00

__ NO 02/14/2023 - 22:00:00 02/15/2023 - 0:00:00

__ NO 02/14/2023 - 20:00:00 02/14/2023 - 22:00:00

Changing the parameter 'View Empty Intervals Y/N' to 'Y' doesn't have any impact on the response time.

Workaround:-

After deleting the empty intervals(by reducing the retention period) the performance of CQMINTV command had reduced from 10mins to 8 seconds. This was witnessed when we cut down the retention period from 52 days to 40 days. But the actual problem was not with the number of days the backstore datasets are being retained but the number of empty intervals we had before.