Sequentially processing data in a cached data storage system
US4882642A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1987 |
| Grant date | Nov 21, 1989 |
| Priority date | — |
| Expiry date | Jul 2, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/6026
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The disclosure relates to sequential performance of a cached data storage subsystem with a minimal control signal processing. Sequential access is first detected by monitoring and examining the quantity of data accessed per unit of data storage (track) across a set of contiguously addressable tracks. Since the occupancy of the data in the cache is usually time limited, this examination provides an indication of the rate of sequential processing for a data set, i.e., a data set is being processed usually in contiguously addressable data storage units of a data storage system. Based upon the examination of a group of the tracks in a cache, the amount of data to be promoted to the cache from a backing store in anticipation of future host processor references is optimized. A promotion factor is calculated by combining the access extents monitored in the individual data storage areas and is expressed in a number of tracks units to be promoted. The examination of the group of tracks units and the implementation of the data promotion and demotion (early cast-out) is synchronized which results in a synergistic effect for increasing throughput of the cache for sequentially-processed data. A…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.