Patent
1995-12-12
1998-03-31
Swann, Tod R.
395404, 395440, 395463, 395487, 395492, 39549701, 395622, 395876, G06F 1212
Patent
active
057348618
ABSTRACT:
A log-structured array (LSA) includes a relatively large, non-volatile cache memory as well as a memory segment write buffer. The LSA cache memory contains both updated logical tracks received from the host system and also clean logical tracks read from direct access storage devices of the array. When the fraction of updated tracks in the cache memory exceeds a threshold value, updated tracks are moved from the LSA cache memory to the memory segment. With each modified track to be moved, adjacent modified tracks also are moved. The updated tracks are moved regardless of their location in the updated LRU list. Clean tracks in the LSA cache memory are moved into the memory segment as well, when additional clean tracks are needed in the cache memory. The clean tracks are selected from the bottom of the LSA cache clean track LRU list. Checking for adjacency also can occur at garbage collection time, performed in a background mode. The criterion for determining logical adjacency can use information from the host computer and can be changed dynamically to optimize performance.
REFERENCES:
patent: 4914656 (1990-04-01), Dunphy, Jr. et al.
patent: 4916605 (1990-04-01), Beardsley et al.
patent: 5083229 (1992-01-01), Frey, Jr.
patent: 5124987 (1992-06-01), Milligan et al.
patent: 5416915 (1995-05-01), Mattson et al.
patent: 5418921 (1995-05-01), Cortney et al.
patent: 5422762 (1995-06-01), Jerbie
patent: 5442752 (1995-08-01), Styczinski
patent: 5542066 (1996-07-01), Mattson et al.
patent: 5551002 (1996-08-01), Rosich et al.
patent: 5551003 (1996-08-01), Mattson et al.
"Strage (sic) System", JAPIO, abstract of Patent No. JP 07-44326.
"Disk Array Device", JAPIO, abstract of Patent No. JP 07-36634.
"A Case for Redundant Arrays of Inexpensive Disks (RAID)", by David A. Patterson, Garth Gibson, and Randy H. Katz, Report No. UCB/CSD 87/391, University of California (Berkeley), Dec. 1987, pp. 1-22.
"The Design and Implementation of a Log-Structured File System", by Mendel Rosenblum and John K. Ousterhout, ACM Transactions on Computer Systems, vol. 10, No. 1, Feb. 1992, pp. 26-51.
"Automatic Tuning of Data Placement and Load Balancing in Disk Arrays", by Peter Scheuermann, Gerhard Weikum, and Peter Zabback, Apr. 1992, pp. 3-22.
"Adaptive Load Balancing in Disk Arrays", by P. Scheuermann, et al., in Foundations of Data Organization and Algorithms, 4th Int'l. Conference, Oct. 13-15, 1993, D. Lomet (Ed.), pp. 344-361.
"Data Set Affinity Matrix Program", R. Ascherfield, C. Raby, IBM Technical Disclosure Bulletin, Vo. 27, No. 10B, Mar. 1985, pp. 6142-6143.
"Disk Array Device", Japanese Patent Information Organization (JAPIO), abstract of Patent No. 06-175787.
"Data Storing System for Disk Array Device", JAPIO, abstract of Patent No. JP 06-214722.
"Disk Array Device and Its Control Method", JAPIO, abstract of Patent No. JP 07-44331.
Cohn Oded
Mattson Richard Lewis
Menon Jaishankar Moothedath
International Business Machines - Corporation
Kim Hong C.
Swann Tod R.
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