Data organization and storage hierarchies in a multimedia server

The authors present the data organization and storage hierarchy support in the OVM object-oriented multimedia database kernel. Data in the OVM (object virtual machine) are organized in three layers: the logical file layer, the physical file layer, and the device layer. The data organization on devices allows for multilevel storage hierarchies, support for removable disks, parallel access, and storage transparency. The implementation model of the Storage Machine (SM), the storage manner of OVM, is presented. The current version of SM consists of more than 20000 lines of C++ source code, developed on Sun 4 workstations (SunOS 4.0 and 4.1), and ported to HP workstations (HP-UX 8.05) and PCs (PC-DOS).<
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