US5375233A
Expired / Lapsed
US
⏱️ 0.0 years remaining
File system
Assignee: Fujitsu Services Ltd
•
Filing: 1992-04-06
•
Granted: 1994-12-20
•
Expires: 2012-04-06
Abstract
Abstract A disc file system is described in which the disc space is divided into very large blocks of at least 64k bytes. A large file is allocated a whole number of these large blocks, contiguously where possible. Small files reside in small file areas each of which is composed of a number of large blocks. Space in these small file areas is allocated in multiples of a small block size (e.g. 4K bytes). The use of large and small blocks reduces the wastage of space that would occur if small files were written into large blocks. The amount of head movement when reading large amounts of data from large files is reduced because of the large block size and because the large blocks are allocated contiguously.
Inventors
- 👤 Susan P. Kimber
- 👤 Andrew J. McPhee
- 👤 John C. Moor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:08
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/06; G06F3/0601; G06F3/0668; G06F3/0671; G06F3/0673; G06F3/0674; G06F16/00; G06F16/90; G06F16/901; G06F16/9017; G06F3/0602; G06F3/061; G06F3/0613; G06F3/0628; G06F3/0638; G06F3/0643; Y; Y10; Y10S; Y10S707/00; Y10S707/99951; Y10S707/99956
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
313 words
In a data processing apparatus, a method of storing data files in a disk file wherein each of said files when it is created is designated as a large file or a small file and wherein said disk file contains storage space comprising a plurality of large blocks of equal size, the method comprising creating at least one small file area on demand when required, each said small file area being created out of an integral number of said large blocks, each large block in each small file area being divided into a plurality of small blocks, the method further comprising extending a data file by means of the following steps: (a) operating the data processing apparatus to determine whether the file to be extended has been designated when it was created as a large file or a small file, (b) in the event that the apparatus determines that the file to be extended has been designated as a large file, allocating an integral number of said large blocks to that file, (c) in the event that the apparatus determines that the file to be extended has been designated as a small file and there exists available free space in an existing small file area, allocating an integral number of said small blocks from said existing small file area to the file to be extended, and (d) in the event that the apparatus determines that the file to be extended has been designated as a small file and no available free space exists in an existing small file area, creating a new small file area and allocating an integral number of small blocks from said new file area to the file to be extended, (e) whereby files designated as large files are extended only by addition of large blocks and files designated as small files are extended only by addition of small blocks.
Claim 2
Dependent Claim
313 words
In a data processing apparatus, a method of storing data files in a disk file wherein each of said files when it is created is designated as a large file or a small file and wherein said disk file contains storage space comprising a plurality of large blocks of equal size, the method comprising creating at least one small file area on demand when required, each said small file area being created out of an integral number of said large blocks, each large block in each small file area being divided into a plurality of small blocks, the method further comprising extending a data file by means of the following steps: (a) operating the data processing apparatus to determine whether the file to be extended has been designated when it was created as a large file or a small file, (b) in the event that the apparatus determines that the file to be extended has been designated as a large file, allocating an integral number of said large blocks to that file, (c) in the event that the apparatus determines that the file to be extended has been designated as a small file and there exists available free space in an existing small file area, allocating an integral number of said small blocks from said existing small file area to the file to be extended, and (d) in the event that the apparatus determines that the file to be extended has been designated as a small file and no available free space exists in an existing small file area, creating a new small file area and allocating an integral number of small blocks from said new file area to the file to be extended, (e) whereby files designated as large files are extended only by addition of large blocks and files designated as small files are extended only by addition of small blocks.
Claim 3
Dependent Claim
18 words
A method according to claim 1 wherein each said large block is at least 64 Kbytes in size.
Claim 4
Dependent Claim
19 words
A method according to claim 1 wherein each said large file is allocated physically contiguous large blocks wherever possible.
References Cited (Backward Citations)
US4435752A
Cited
US4121286A
Cited
US4164026A
Cited
US4536837A
Cited
US4849878A
Cited
JPS61138363A
Cited
US4843570A
Cited
JPS62221048A
Cited
JPS62236049A
Cited
US4800550A
Cited
US4945475A
Cited
US4947367A
Cited
US5021946A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-12-19 | 1998-06-20 | 1998-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-12-19 | 2002-06-20 | 2002-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-12-19 | 2006-06-20 | 2006-12-20 | $7700.00 | Window Closed / Lapsed |