Title:
DISK CACHE CONTROL METHOD, DISK ARRAY DEVICE, AND STORAGE DEVICE
Document Type and Number:
WIPO Patent Application WO/1999/040516
Kind Code:
A1
Abstract:
The LRU method which is currently used as a standard method for cache control is not able to provide efficient control in such an environment that a disk array is used, namely, a plurality of applications operate in a multiplexed state, because the method only uses access frequencies for the control. Therefore, a volume is divided into a plurality of areas having a plurality of arbitrary fixed lengths and access frequencies are acquired at every divided area and, at the time of assigning a disk cache, the disk cache is controlled so that the areas can be deprived in the order of access frequencies from the area having the lowest frequency. Consequently, the hit rate of disk caches can be improved by performing disk cache control in accordance with the access characteristic.
Inventors:
TAKAMOTO YOSHIFUMI (JP)
OBARA KIYOHIRO (JP)
OBARA KIYOHIRO (JP)
Application Number:
PCT/JP1998/000463
Publication Date:
August 12, 1999
Filing Date:
February 04, 1998
Export Citation:
Assignee:
HITACHI LTD (JP)
TAKAMOTO YOSHIFUMI (JP)
OBARA KIYOHIRO (JP)
TAKAMOTO YOSHIFUMI (JP)
OBARA KIYOHIRO (JP)
International Classes:
G06F12/08; G06F12/0866; G06F12/12; G06F12/121; G06F12/122; (IPC1-7): G06F12/08; G06F12/12
Foreign References:
| JPH0492941A | 1992-03-25 | |||
| JPS63280356A | 1988-11-17 | |||
| JPH0331948A | 1991-02-12 | |||
| JPH04259048A | 1992-09-14 | |||
| JPH08115263A | 1996-05-07 |
Other References:
See also references of EP 1061449A4
Attorney, Agent or Firm:
Ogawa, Katsuo (5-1, Marunouchi 1-chom, Chiyoda-ku Tokyo, JP)
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