EP0273665A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
System for write once read many optical storage devices to appear rewritable
Assignee: General Electric Co
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Filing: 1987-12-21
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Granted: —
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Expires: 2007-12-21
Abstract
Abstract A system for Write Once Read Many (WORM) optical storage devices to appear rewritable used magnetic disk storage and optical WORM storage subsystem. All new write operations are made to a magnetic cache storage (28) which resides on the magnetic disk subsystem. A Least Recently Written (LRW) technique is used to determine which valid data in cache storage is the oldest, and this is transferred to the WORM storage (30) when room for new data is required. In this manner all new write operations are performed to the magnetic cache storage and only the oldest valid data is transferred to WORM storage optimizing its use.
Inventors
- 👤 Phillip Warren Jones
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 19:41
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/12; G11B20/1217; G06; G06F; G06F12/00; G06F12/02; G06F12/08; G06F12/0802; G06F12/0866; G06F12/12; G06F12/121; G06F12/126; G11B2020/10898; G11B2020/10907; G11B2220/00; G11B2220/40; G11B2220/45; G11B2220/455
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
103 words
An apparatus for increasing the utility of a Write Once Read Many (WORM) storage medium characterized by the combination of: cache storage means (28) for storing data; WORM storage means (30) for storing data; and caching system controller means (26) operatively coupled to said cache and WORM storage means for determining where in said cache storage means new data is to be written and which data currently stored therein is to be transferred to said WORM storage means to make room for the new data, so as to minimize the number of write operations to said WORM storage means and increase its utility.
Claim 2
Independent Claim
103 words
An apparatus for increasing the utility of a Write Once Read Many (WORM) storage medium characterized by the combination of: cache storage means (28) for storing data; WORM storage means (30) for storing data; and caching system controller means (26) operatively coupled to said cache and WORM storage means for determining where in said cache storage means new data is to be written and which data currently stored therein is to be transferred to said WORM storage means to make room for the new data, so as to minimize the number of write operations to said WORM storage means and increase its utility.
Claim 3
Dependent Claim
58 words
Apparatus as in Claim 1 wherein said caching system controller means (26) includes means for determining the least recently written data in said cache storage means and means for transferring said least recently written data, if it is valid, to said WORM storage means to make room for new data to be written in said cache storage means.
Claim 4
Dependent Claim
18 words
Apparatus as in Claim 2 or 2 wherein said WORM storage means (30) comprises an optical storage subsystem.
Claim 5
Dependent Claim
19 words
Apparatus as in Claim 1, 2 or 3 wherein said cache storage means (28) comprises a magnetic storage subsystem.
Claim 6
Dependent Claim
29 words
Apparatus as in any preceding claim wherein said caching system means comprises content addressable memory means for storing data address information of data stored in said cache storage means.
Claim 7
Dependent Claim
35 words
Apparatus as in any preceding claim including "scrub" means (Figs 4 and 6) associated with said WORM storage means for effectively replacing old data therein with new data transferred thereto from the cache storage means.
References Cited (Backward Citations)
No citation records indexed.
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