Patent · US Expired

Queue ordering for memory and I/O transactions in a multiple concurrent transaction computer system

US5905876A · kind A · utility

117Cited by
13References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 16, 1996
Grant dateMay 18, 1999
Priority date
Expiry dateDec 16, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/0835
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A transaction ordering mechanism for processor-based computing systems ensures proper ordering of transactions between the processor, I/O and memory subsystems, ensures cache coherence within the computing system, and facilitates concurrence of the transactions so as to enable high-bandwidth, deadlock-free operation. I/O to memory transactions and processor to memory transactions are placed in a memory request queue in the order in which such transactions appear on the processor bus; I/O to memory transactions are placed in an inbound request queue in the order such transactions appear on the I/O bus; and processor to I/O transactions and completions corresponding to split-transaction I/O to memory read transactions are placed in an outbound request queue in the order in which the split-transaction I/O to memory read transactions and the processor to I/O transactions appear on the processor bus.

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