Multiprocessing system employing address switches to control mixed broadcast snooping and directory based coherency protocols transparent to active devices
US7222220B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 2003 |
| Grant date | May 22, 2007 |
| Priority date | — |
| Expiry date | Aug 25, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/0831
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A multiprocessor computer system is configured to selectively transmit address transactions through an address network using either a broadcast mode or a point-to-point mode transparent to the active devices that initiate the transactions. Depending on the mode of transmission selected, either a directory-based coherency protocol or a broadcast snooping coherency protocol is implemented to maintain coherency within the system. A computing node is formed by a group of clients which share a common address and data network. The address network is configured to determine whether a particular transaction is to be conveyed in broadcast mode or point-to-point mode. In one embodiment, the address network includes a mode table with entries which are configurable to indicate transmission modes corresponding to different regions of the address space within the node. Upon receiving a coherence request transaction, the address network may then access the table in order to determine the transmission mode, broadcast or point-to-point, which corresponds to the received transaction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.