Coherency maintenance in a multiprocessor system
US6275906A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 1999 |
| Grant date | Aug 14, 2001 |
| Priority date | — |
| Expiry date | May 20, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/0831
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A memory subsystem for use with a multiprocessor computer system. The memory subsystem includes an operation block adapted for queuing an operation that misses in an L1 cache of a multiprocessor. The multiprocessor is comprised of a set of processors, preferably fabricated on a single semiconductor substrate and packaged in a single device package. The memory subsystem further includes an arbiter that is configured to receive external snoop operations from a bus interface unit and a queued operation from the operation block. The arbiter is configured to select and initiate one of received operations. Coherency is maintained by forwarding the address associated with the operation selected by the arbiter to each of a plurality of coherency units. In this manner, external and internal snoop addresses are arbitrated at a single point to produce a single subsystem snoop address that is propagated to each coherency unit. Preferably, the operation block includes a load miss block suitable for queuing load type operations and a store miss block suitable for queuing store type operations. In one embodiment, the subsystem includes a unidirectional local interconnect suitable for connecting t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.