The information management system IMS/VS, Part V: Transaction processing facilities
William C. Mcgee · IBM Systems Journal · 1977
Two general categories of transaction processing facilities are provided in IMS/VS: the DC transaction processing facilities that had their origin in early IMS systems, and are intended for a broad range of transaction processing applications; and the FP transaction processing facilities, a more recent addition, that are intended for applications with high transaction volumes and limited processing. DC transactions are queued by type, and are removed from the queues by user-written programs that are scheduled by the operator or by the TMS/VS control program, on the basis of transaction priorities and resource availability. FP transactions are queued by load balancing group, and are processed by operator-initiated executions of user-written programs. Both types of transaction processing may coexist in the same on-line execution.