Electrical computers and digital processing systems: memory – Storage accessing and control – Specific memory composition
Patent
1996-07-30
1998-05-05
Asta, Frank J.
Electrical computers and digital processing systems: memory
Storage accessing and control
Specific memory composition
711128, 711133, 711141, 711146, 364DIG1, G06F 1300
Patent
active
057490872
ABSTRACT:
A method and apparatus are provided for maintaining a N-way associative directory utilizing a content addressable memory (CAM). A congruence class from the N-way associative directory including a directory entry identified for a data operation is read into the CAM for the data operation. The directory entry for the data operation in the CAM is locked while the data operation is pending. Other entries in the congruence class are available. When the data operation is completed, checking for a state change is performed. Responsive to an identified state change, the directory entry for the data operation in the CAM is updated or marked as changed. The congruence class including the updated directory entry is marked as dirty. In accordance with features of the invention, the changed congruence class directory entries in the CAM are accumulated and scheduled to be written back to the N-way associative directory. The congruence classes including the changed directory entries in the CAM are written back to the N-way associative directory when the N-way associative directory is idle. After the congruence classes including the changed directory entries in the CAM are written back to the N-way associative directory, these CAM entries are marked as not busy and not dirty and can be reused.
REFERENCES:
patent: 4587610 (1986-05-01), Rodman
patent: 4914577 (1990-04-01), Stewart et al.
patent: 4972338 (1990-11-01), Crawford et al.
patent: 5249282 (1993-09-01), Segers
patent: 5261106 (1993-11-01), Lentz et al.
patent: 5329405 (1994-07-01), Hou et al.
patent: 5383146 (1995-01-01), Threewitt
patent: 5404482 (1995-04-01), Stamm et al.
patent: 5404483 (1995-04-01), Stamm et al.
patent: 5414704 (1995-05-01), Spinney
patent: 5457788 (1995-10-01), Machida
patent: 5504874 (1996-04-01), Galles et al.
patent: 5530958 (1996-06-01), Agarwal et al.
patent: 5537623 (1996-07-01), Chamberlain et al.
Hoover Russell D.
Nation George W.
Valk Kenneth M.
Asta Frank J.
International Business Machines - Corporation
Pennington Joan
LandOfFree
Method and apparatus for maintaining n-way associative directori does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for maintaining n-way associative directori, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for maintaining n-way associative directori will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-71701