MARC: MVS archival storage and recovery program
James P. Considine, Jr. J. Paul Myers · IBM Systems Journal · 1977
MARC has been operating at IBM Hursley and Yorktown Heights since early 1976, and at the IBM acility in Burlington, Vermont since September, 1976. As of January, 1977, there were about eleven thousand migrated data sets at Hursley, and about twelve thousand at Yorktown Heights. The Level 0 on-line storage at Yorktown Heights, for example, contains approximately two thousand three hundred data sets. Implementation problems that we have experienced are mainly those of understanding the MVS system and the interfaces between it and our code. In addition, as a result of the number of subtasks that execute in the MARC address space, we have had problems in correctly sharing serially reusable resources. To avoid a deadlock between two tasks whose needs might be inextricably entwined, we have had to pay close attention to the order and type of enqueuing of the data sets and other resources that are used by MARC tasks.