Method of controlling data transfer and a safe shutdown in a hierarchical cache system during power cut-off
US5761406A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 11, 1997 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Aug 11, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/1021
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for transferring data from one memory to another within a memory hierarchy in a data processing system. The memory hierarchy includes a random access memory (RAM) cache within a control unit and a lower level disk cache memory. When the control unit is in a non-operating (non-printing) state, data to be saved (character-image data) in the RAM cache memory is transferred to the disk cache memory at regular intervals in order of priority, thereby saving the data in the disk cache memory. If a power supply is cut off and then power is reintroduced, high-priority character-image data, which has been transferred from the RAM cache memory to the disk cache memory and saved in the disk cache memory when printing is not being carried out, is restored in the RAM cache memory. As a result, the high-priority data saved in the RAM cache memory when the power supply was cut off can be restored in the RAM cache memory, thereby raising the hit rate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.