Goodman, JamesHum, HHJ2012-02-2220092009. 23 pageshttp://hdl.handle.net/2292/11594We describe MESIF, the first source-snooping cache coherence protocol. Built on point-to-point communication links, the protocol maintains no directory, and mimics the broadcast behavior of a snooping cache protocol. MESIF supplies data cached in other nodes in a single round-trip delay (2-hop latency) for all common operations. Because of the speed of the links, the protocol can outperform a bus-based protocol for a small number of nodes, but scales through hierarchical extension to a large-scale multiprocessor system. Salient features of the protocol are described. The introduction of a novel forwarding state is used to assure a single response to shared data and to simplify conflict resolution. In the hierarchical extension, auxiliary hardware data structures can be included to provide 2-hop latency for most operations. The recently revealed Intel® Quick-Path InterconnectTM protocol is derived from MESIF. Some design differences are highlighted.Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher.https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htmcache coherencyMESIFReporthttp://purl.org/eprint/accessRights/OpenAccess