Patent · US Expired

Cache coherence protocol with speculative writestream

US7376793B2 · kind B2 · utility

4Cited by
4References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 21, 2005
Grant dateMay 20, 2008
Priority date
Expiry dateApr 26, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/0855
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A system and method for performing speculative writestream transactions in a computing system. A computing system including a plurality of subsystems has a requesting subsystem configured to initiate a writestream ordered (WSO) transaction to perform a write operation to an entire coherency unit by conveying a WSO request to a home subsystem of the coherency unit. The requester is configured to perform the write operation without first receiving a copy of the coherency unit and complete WSO transactions initiated in the order in which they are initiated. The home subsystem is configured to process multiple WSO transactions directed to a given coherency unit in the order in which they are received. When the requester initiates a WSO transaction to a given coherency unit, the coherency unit is locked. Responsive to receiving the WSO request, the home subsystem conveys a pull request for the write data to the requester. If the requester detects a timeout condition, the requester may cancel the WSO transaction and unlock the coherency unit in the requesting node. The requester may further convey an acknowledgment to the home subsystem indicating no data will be returned. The home subsy…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.