CICS® BMS allows you to use different versions of a map set for different device types by specifying a one-letter suffix for each different device type. Use of this facility requires the BMS device-dependent suffix (DDS) option. For further information on map set suffixes, see the CICS Application Programming Guide.
Where only one version of a map is involved, it is optional whether the device type suffix is coded. If the DDS option is being used, it is more efficient to use the device suffixes than to leave the suffix blank. This is because, if the DDS option applies, CICS first looks for a map set with a suffix name and then searches again for a map with a blank suffix. Processor cycle requirements are reduced by eliminating the second table lookup.
If only one device type is used with all maps in a CICS system and all devices have the same screen size, CICS can be initialized to look for a blank suffix, thus eliminating the second lookup.
If the map is to be used with multiple devices, multiple maps with the same basic source are needed because the device type needs to be specified, and suffixing is required in this case.
If you decide that you need device-dependent suffixing, you should suffix all your map sets. If you do not need it, use blank suffixes (no suffix at all) and specify the NODDS option in BMS.
Maps are named in the link-edit process. These names are defined in the MAPSET definition. Specifying NODDS in the BMS= system initialization parameter determines that map suffixing is not used in CICS.
No direct measurement of map suffixing is given.