Looking at moving MIA controlfile from real DASD to CF. We have plenty of spare capacity in our CF's.
As its only for MIA is there any structure sizing information?
Release : 12.5
Component : MIA
IBM doc describing CF sizing requirements can be found here
Excerpt: "The size of a coupling facility structure includes the total amount
of storage required by both the application and by the coupling facility
itself for structure control information, and is specified in size units of kilobytes, megabytes, gigabytes or terabytes.
Determining the correct size is based on the application's use of
the structure, characteristics of the workload environment in which
the structure is to be used, and the CFLEVEL of the coupling facility
in which the structure is allocated."
So in general, converting the DASD space allocation to bytes and adding extra for the structure itself (perhaps twice what the Control File uses) would work, but for MIA it can be simpler.
Bottom line: The default sizing in the CBDTJCL(ALLOCSTR) job is more than enough for MIA.