Use the EDG_EXIT100 installation exit to request that DFSMSrmm records information about the first data set only and keeps track of the statistics at the volume level. DFSMSrmm then performs data set name checking on the first data set only. DFSMSrmm does not keep track of the number of data sets on the volume when data set recording is turned off for a volume. DFSMSrmm keeps track of some items like the use count to reflect the number of times the volume is read or written. You must request that DFSMSrmm records only the first data set each time you rewrite the first data set. Otherwise DFSMSrmm resumes recording information about all the data sets on the volume.

If you have applications that create multiple cataloged data sets on tape, and you suppress the DFSMSrmm recording of other than the first data set on the volume, ensure that the data sets other than the first data set are uncataloged. When the recording of data set information is suppressed, DFSMSrmm does not uncatalog these data sets during inventory management processing when the parmlib option UNCATALOG is specified as S or Y. Since DFSMSrmm cannot uncatalog the data sets, another method must be used to uncatalog them. Leaving non-existent data sets cataloged could lead to processing problems later.