Dynamically adaptive data retrieval for a disk drive storage system
US5742789A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 1995 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Dec 28, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/312
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for retrieving a data file from a disk drive storage which provide for overlapping read operations thereby reducing the latency seen by a requesting host computer. The host computer requests the retrieval of a data file and a channel director places that request in a data cache. If the data file is not in the data cache, a disk director reads and transfers the data file from the disk drive to the data cache. At a certain point in the transfer of the data file into the data cache, the disk director places a start read message in the data cache which is then read by the channel director. Upon receipt of the start read message, the channel director begins to read the data file from the data cache, thus reading data from the data cache as the disk director completes writing the data file to the data cache. The channel director can adaptively modify the starting point for reading the data files depending upon the "success" rate of previous read operations. The success rate translates into increasing or decreasing a parameter representing the percentage of the data file which must be placed in data cache before the channel director can begin reading from the cache…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.