System and method for providing variable sector-format operation to a disk access system
US5813025A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 1996 |
| Grant date | Sep 22, 1998 |
| Priority date | — |
| Expiry date | Dec 2, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0674
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system and method are disclosed for providing computers, particularly the Unisys A series computers, with the capability to function with disk drives of more than one sector format, especially if a predetermined sector format is inefficient and/or cost prohibitive. Interfacing is provided for processing I/O requests between a predetermined logical sector format (e.g., 180 byte sectors) and a variable physical sector format (e.g., 512 or 720 byte sectors). Read operations compare read request addresses to physical sector boundaries and discard unwanted data. Write operations, using at least one sector buffer, perform a read/modify/write cycle, such that the necessary physical sector data not associated with the write request is read into the sector buffer, modified and written back to the disk along with the write data inserted at the appropriate location. This system and method can effectively increase the usable capacity of selected disk drives by 15-20%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.