Method and apparatus having a snoop filter decoupled from an associated cache and a buffer for replacement line addresses
US9058272B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2013 |
| Grant date | Jun 16, 2015 |
| Priority date | — |
| Expiry date | Dec 19, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D10/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An apparatus including a snoop filter decoupled from a cache and an associated method for snoop filtering are disclosed. The snoop filter is decoupled from the cache such that the cache changes states of lines in the cache from a first state that is a clean state, such as an exclusive (E) state, to a second state that is not a clean state, such as a modified (M) state, without the snoop filter's knowledge. The snoop filter buffers addresses of replaced lines that are unknown to be clean until a write-back associated with the replacement lines occurs, or until actual states of the replaced lines are determined by the snoop filter generating a snoop. A multi-level cache system in which a reallocation or replacement policy is biased to favor replacing certain lines such as inclusive lines, non-temporal lines or prefetched lines that have not been accessed, is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.