Method and apparatus for replacing cache lines in a cache memory
US6490654B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1998 |
| Grant date | Dec 3, 2002 |
| Priority date | — |
| Expiry date | Jul 31, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F21/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A cache memory replacement algorithm replaces cache lines based on the likelihood that cache lines will not be needed soon. A cache memory in accordance with the present invention includes a plurality of cache lines that are accessed associatively, with a count entry associated with each cache line storing a count value that defines a replacement class. The count entry is typically loaded with a count value when the cache line is accessed, with the count value indicating the likelihood that the contents of cache lines will be needed soon. In other words, data which is likely to be needed soon is assigned a higher replacement class, while data that is more speculative and less likely to be needed soon is assigned a lower replacement class. When the cache memory becomes full, the replacement algorithm selects for replacement those cache lines having the lowest replacement class. Accordingly, the cache lines selected for replacement contain the most speculative data in the cache that is least likely to be needed soon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.