how to figure out the size in MB for an informix database

acutal_size = free * 4096 = bytes

/ 1024 = Kbytes
/ 1024 = Mbytes
/ 1024 = GBytes.

Thats makes the total size of a chunk at 0.9gb

Free:

692mb
944mb
621mb
194mb

Do these numbers seem familiar? Plug them into a spread sheet for more accurate results.

Plus, be very careful when changing the disk allocations of logical volumes underneath Informix' nose. If you screw up, Informix won't like it and a level 0 archive/restore might not cut it either. Do a dbexport to disk or tape. It may take a while, and the restoration, with dbimport, may be a bit trickier with large tables. The benefit would be that the format (dbschema + unload files) is simple and does not rely on the underlying instance configuration on being exactly the same.