公开(公告)号：JPH10124394A

公开(公告)日：1998-05-15

申请号：JP20637097

申请日：1997-07-31

Applicant: IBM

Inventor： HERGER LORRAINE MARIA PAOLA ,  KUON-KEN MAKU ,  KENNETH BLAIR OCHERTLY ,  TO CHII TSUAI ,  MICHAEL EDWARD WAZHLOVSKIJ

IPC: G06F12/08

Abstract: PROBLEM TO BE SOLVED: To minimize the number of chips required to be designed to constitute a system by invalidating all other cached copies so as to write data in an exclusive copy by using bus information stored in a directory at the time of acquiring the exclusive copy. SOLUTION: Exclusive reading operation is outputted by a processor 13-5 in order to request an exclusive information access. A mutual connection part 1-2 starts a process for invalidating other copies of information based on the exclusive reading operation, and when the process is cached, the information is returned or reading operation is transmitted on a bus including the information. Since the information is a global shared state, the copy of the information are stored in another position of the system and invalidation operation is propagated from the port of the mutual connection part 1-2 to an L port formed on the right end of a mutual connection part 1-3. At the time of receiving the invalidation operation, the mutual connection part 1-3 outputs invalidation ACK to the port and sends the invalidation operation to an L port formed on the left end.

公开(公告)号：GB2316204A

公开(公告)日：1998-02-18

申请号：GB9715399

申请日：1997-07-23

Applicant: IBM

Inventor： HERGER LORRAINE MARIA PAOLA ,  MAK KWON-KEN ,  OCHELTREE KENNETH BLAIR ,  TSAI TU-CHIH ,  WAZLOWSKI MICHAEL EDWARD

IPC: G06F12/08

Abstract: Multiple processors 13-1 - 13-8 with associated caches 14-1 - 15-8 are connected through a plurality of interconnects 1-1 - 1-3, typically arranged in a hierarchical tree, to a shared memory 9. Each interconnect has multiple Local ports 3 that connect either to processors or to other interconnects, and a Global port 4 connected to a Local port of another interconnect, and a directory 11 in each interconnect has a routing record, for each line of storage in the system memory, having an entry for each port to indicate whether a copy of the line is being held by a processor or memory reached through that port. Information is shared in caches in the system using these path indicators in the directories, and, when a processor acquires a copy of information exclusively, it uses the path indicators to invalidate all the other cached copies so that it can write to an exclusive copy.