The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 08, 1998
Filed:
Dec. 09, 1996
Gene F Young, Lexington, SC (US);
Roy M Stevens, Lexington, SC (US);
Larry C James, West Columbia, SC (US);
Intel Corporation, Santa Clara, CA (US);
Abstract
A directory-based cache coherency memory system for a multiprocessor computer system. The memory system includes a system memory shared by the multiple processors within the computer system; a plurality of data cache memories, at least one data cache memory associated with each processor; a system of busses interconnecting the system memory with the plurality of data cache memories and processors, and a state cache memory associated with the shared system memory for the storage of memory line state information identifying where within the system memory and the plurality of data cache memories the most current copy of a line of memory resides. The state cache memory is sized to store state information for only a portion of the memory lines included in system memory, e.g., one sixteenth of the memory lines contained in system memory, in recognition that rarely will all of system memory be utilized (cached) at any one time. The state cache can be a direct mapped cache wherein state information for an associated line of memory is stored within the state cache together with a tag field being a first portion of the address of the associated line of memory, and indexed within the state cache by the remaining portion of the address.