Since API tables do not have the concept of soft-delete, we purge
the instance_mappings, request_specs and instance_group_member records
of deleted instances while they are archived. The ``nova-manage db
archive_deleted_rows`` offers a ``max-rows`` parameter which actually
means the batch size of the iteration for moving the soft-deleted
records from table to their shadow-tables. So this patch clarifies
that the batch size does not include the API table records that are
purged so that the users are not confused by the ``--verbose`` output
of the command giving more rows than specified.
Change-Id: I652854c7192b996a33ed343a51a0fd8c7620e876
Closes-Bug: #1794994
Surya Seetharaman
660f717394