Optimal Reorganization of Distributed Space Disk Files In most database organizations, the cost of accessing the database will increase due to structural changes caused by updates and insertions. By reorganizing the database,the access costs can be reduced. A basic problem is to establish the proper tradeoff between performance, storage costs, and reorganization costs. This paper considers the optimum points at which to reorganize a database. A disk file organization which allows for distributed free space is described. A cost function describing the excess costs due to physical disorganization is defined, and this function is minimized to obtain the optimum reorganization points. Numerical examples based on the characteristics of existing disk storage devices are given. CACM November, 1976 Maruyama, K. Smith, S. E. disk file, free space,retrieval, insertion, deterioration, reorganization 3.70 3.73 CA761107 JB January 3, 1978 2:59 PM 2816 4 2816 2816 4 2816 2816 4 2816 2828 4 2816 2827 4 2816 2913 4 2816 3047 4 2816 3047 4 2816 3129 4 2816 2493 5 2816 2751 5 2816 2816 5 2816 2816 5 2816 2816 5 2816 2829 5 2816 3129 5 2816 2493 6 2816 2816 6 2816