Observations of a firm's information processing with a data base management system

The organization in this study used all versions of IMS, from IMS 1 through IMS VS 1.01, over the period 1970–1975. During this period, the number of messages processed steadily increased from 6000 in October 1970 to a maximum in excess of 150,000 in September 1974. This volume enhancement was achieved by solving a sequence of problems concerning IMS software, data base design, or program coding. Perhaps the most important factors supporting the increase were two improvements in IMS software: one was the data base buffer pool introduced with IMS 2; the other the feature introduced with IMS VS that, unlike the previous versions, enabled the simultaneous updating of different data base segments belonging to the same type.