Electrical computers and digital processing systems: memory – Storage accessing and control – Access timing
Patent
1998-02-02
2000-08-15
Cabeca, John W.
Electrical computers and digital processing systems: memory
Storage accessing and control
Access timing
163151, 163158, 163122, G06F 1200
Patent
active
061051187
ABSTRACT:
The invention is a system, method, and computer readable medium for determining which copy of data to access in an information handling system. Since the same data is often stored in more than one storage location (e.g., on more than one physical volume or disk, or in more than one memory area), it is often more efficient to read a particular copy of the data. The present invention determines which copy of the desired data can be read most efficiently (i.e. in the least amount of time), and then accesses that particular copy of the data. In an embodiment of the invention, when a read request is received, each mirrored disk (i.e. copy) containing the requested data is checked to determine which disk contains the fewest relocated blocks within the desired read area. The data is then read from the mirrored disk with the fewest relocated blocks within the read area. The present invention decreases the amount of time it takes to perform I/O operations in an information handling system, as the data copy which is read is the one which can be read in the least amount of time.
REFERENCES:
patent: 5239643 (1993-08-01), Blount et al.
patent: 5390313 (1995-02-01), Yanai et al.
patent: 5519844 (1996-05-01), Stallmo
patent: 5548711 (1996-08-01), Brant et al.
patent: 5636359 (1997-06-01), Beardsley et al.
patent: 5708769 (1998-01-01), Stallmo
patent: 5819310 (1998-10-01), Vishlitzky et al.
patent: 5937428 (1999-08-01), Jantz
IBM TDB "Selecting Mirrored Disk Unit for Read Operations", vol. 33, No. 4, Sep. 1990, pp. 33-34.
IBM TDB "Automatic Swap of the Primary and Secondary Mirrors in a Disk Mirror System", vol. 36, No. 12, Dec. 1993, pp. 85-86.
IBM TDB "Reduction of Delay Experienced during Mirror Disk Access Failures", vol. 36, No. 12, Dec. 1993, pp. 601-602.
Maddalozzo, Jr. John
McBrearty Gerald Francis
Shieh Johnny Meng-Han
Cabeca John W.
International Business Machines - Corporation
Leeuwen Leslie A.
Tyson Thomas E.
Tzeng Fred F.
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