Abstract:
A method for fast, high-density data storage in a data storage device having plural storage sections that includes overwriting and reformatting of entire storage sections, each having a large storage capacity. New or changed data is written continuously on free storage sites of a particular storage section until it is filled. Data from the newly-filled section is restructured and copied to a target section. Additional data is then stored onto a second storage section while the first storage section is restructured and copied. The previously-filled section may be reformatted to store new data after the second storage section is filled with data. The process may be repeated to allow for continuous data storage.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims the benefit of U.S. Provisional Patent Application No. 60/119,827, filed Feb. 12, 1999, entitled “METHOD FOR DATA STORAGE ORGANIZATION.” This Application claims benefit of U.S. provisional Application Serial No. 60/119.827 filed Feb. 12, 1999. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a method of data storage. In particular, the present invention relates to a method of storing data in which data is written continuously to a section of a storage medium until the storage capacity of the section is reached. Additional data is written to a next section of the medium while the data in the now-filled section is restructured into a target section. The previously-filled section is then initialized such that data may again be written thereto. 
     BACKGROUND OF THE INVENTION 
     Information storage and retrieval has become immensely important as a result of the increased need for information exchange in the modern, high technology society of today. The rapidly growing urge for increased access to information has spurred the development of ever larger and faster data storage and retrieval systems. Many forms of data storage and retrieval systems are utilized to date, however, all data storage systems are designed to store and overwrite each bit individually, or to write only once to the storage medium. These limitations significantly restrict the spectrum, access speed, and therefore the performance of uniquely different data storage arrangements. 
     In view above, and the increasing demand for data storage and fast retrieval, there is a need for a method of data storage that overcomes the limitations of the prior art by providing for higher data density and faster data access. The present invention provides such a method. 
     SUMMARY OF THE INVENTION 
     The present invention describes an organization method for data storage that is applicable to data storage devices that have a high data storage density and fast access speeds. The design is based on a technique that does not revise data sets in a bit-by-bit manner, but rather it stores modifications to written data in free storage space and updates entire sections of large bit quantities all at once. This block update method requires a system of two or more storage sections that will simultaneously store, restructure, organize, and copy data, allowing a continuous flow of data to be stored or retrieved. The method of the present invention enables the development of uniquely different data storage methods and devices with extremely fast access speed and high storage density. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing summary, as well as the following detailed description of the preferred embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings an embodiment that is presently preferred, in which like reference numerals represent similar parts throughout the several views of the drawings, it being understood, however, that the invention is not limited to the specific methods and instrumentalities disclosed. In the drawings: 
     FIG. 1 illustrates the data storage organization method of the present invention for a two-section storage system; 
     FIG. 2 is a flow chart that illustrates the process of restructuring data from a first storage section to a second storage section; 
     FIG. 3 illustrates the data storage organization method of the present invention for a three-section storage system; and 
     FIG. 4 illustrates the data storage organization method of the present invention for a four-section storage system. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is directed to a method of data organization, storage, and retrieval utilizing at least two similar data storage sections. The present method is preferably implemented in a data storage device, such as that disclosed in U.S. patent application Ser. No. 09/337,148, entitled, “Method and Device For Charged Particle Ray Information Storage,” filed Jun. 21, 1999, the disclosure of which is incorporated herein by reference in its entirety. 
     Referring now to FIG. 1, there is illustrated the processes performed in the method for data organization, storage and retrieval, utilizing two similar data storage sections  10 A and  10 B. The method of data storage is performed as follows: new, changed or modified data  12  is written continuously into storage section  10 A, as shown in time frame t 1 . When storage section  10 A reaches a predetermined capacity (e.g., approximately all of the available capacity), additional data  14  continues to be stored from top to bottom in storage section  10 B, while the stored data on storage section  10 A is restructured and copied into storage section  10 B, from bottom to top, as shown in time frame t 2  as data  16 . 
     The data  12  is restructured by evaluating the data  12  to eliminate all of modifications, deletions, etc. performed on the files that comprise the data  12  such that the data  16  written to the storage section  10 B contains only unique occurrences of each distinct file stored in data  12 . For example, if a file name “file.doc” is modified by a user and saved four times within the data  12 , only the most recent version of file.doc will be restructured into data  16 . Similarly, if “file.doc” was deleted, it would not be restructured into data  16 . 
     Referring to FIG. 2, there is illustrated the restructuring procedure in accordance with the present invention. The procedure begins (S. 100 ) when a file allocation table or table of contents  102  is read to determine the contents thereof. The table of contents  102  is preferably maintained at the beginning of each storage section  10 . The table of contents  102  is traversed to determine all occurrences of distinct files (S. 102 ) and an operation performed on the file (e.g., access, modify, delete, rename, etc.) at each occurrence (S. 104 ). Next, the type of operation for each file occurrence is determined (S. 108 ). If the operation was a delete or modify, then the file is not copied over to the target storage section (e.g.,  10 B). If the operation was a file creation operation and no other modifications were made to the file, then it is copied to the target storage section. If the operation was a modification, then it is determined if subsequent modifications were made to the file, and if so, only the most recent version is copied to the target storage medium. In accordance with the process of FIG. 2, stored data is accessed in individual blocks and not on a bit-by-bit basis, which advantageously speeds the processing of the data. 
     Returning again to FIG. 1, after the data  12  of storage section  10 A has been restructured and copied into storage section  10 B (i.e., the target storage section) as data  16 , storage section  10 A is initialized (time frame t 3 )  18  by reformatting the section. In accordance with the device disclosed in U.S. patent application Ser. No. 09/337,148, the section of the storage medium may be formatted by inducing a structural phase transition in the section, such as a change in morphology, topography, composition, defect concentration or adsorbing bonding characteristics under the influence of the particle ray at recording parameters. Storage section  10 A must be refreshed before the data  14  written to storage section  10 B reaches a predetermined level of capacity, at which time new data  12  continues to be stored in storage section  10 A, top to bottom, while the data of section  10 B is restructured and copied into storage section  10 A, bottom to top (time frame t 4 ). Storage section  10 B is then initialized as noted above (time frame t 5 ). This cycle can then start over so that continuous data storage can be achieved. 
     FIG. 3 shows the process of data storage and retrieval, utilizing three similar data storage sections  10 A,  10 B and  10 C. The method of data storage proceeds as follows: new, changed or modified data  12  is written continuously into storage section  10 A, as shown in time frame t 1 . When amount of data in storage section  10 A reaches available of capacity, additional data  14  continues to be stored in storage section  10 C, while the stored data on storage section  10 A is restructured and copied into storage section  10 B, as shown in time frame t 2  as data  16 . The reorganization may be performed in accordance with the procedure of FIG.  2 . 
     After the data  12  of storage section  10 A has been restructured and copied into storage section  10 B, storage section  10 A is reformatted (time frame t 3 )  18  before storage section  10 C reaches its available storage capacity (time frame t 4 ). When storage section  10 C reaches this capacity, the data of section  10 C is restructured  14  and copied into storage section  10 B (target storage section) as data  16  (time frame t 5 ). Section  10 C is then initialized (reformatted)  18  with new data  12  being continuously being stored onto storage section  10 A (time frame t 6 ). Before storage section  10 B is completely filled, it too may then be restructured and copied into the reinitialized empty storage section  10 C (target storage section) as data  16  (time frame t 7 ). The reorganization of storage area  10 B is also performed in accordance with FIG.  2 . This is followed by an initialization of storage section  10 B (time frame t 8 ) which allows for writing of data  14  onto this storage section as shown in time frame t 9 . 
     A variety of combinations can be imagined for the use of three independent storage sections. For example data can be written alternating onto storage sections  10 A and  10 C while restructured data will always be copied back into storage section  10 B for permanent storage. 
     FIG. 4 shows the process of data storage and retrieval utilizing four similar data storage sections  10 A- 10 D. The method of data storage is performed as follows: new, changed or modified data  12  is written continuously and alternating onto storage sections  10 A and  10 C, while data  16  marked for permanent storage is stored onto storage section  10 B, as described in the example of FIG. 3 (see, time frames t 1 -t 6 ). Data is written onto either storage section  10 A or  10 C, while the other of storage section  10 C or  10 A is reinitialized  18 . In addition to the process as described in FIG. 3, the data  16  stored onto section  10 B is restructured at time t 7  and stored onto storage section  10 D (target storage section) as data  20 . Storage section  10 B is then reinitialized and can be utilized for transfer for data from sections  10 A and  10 C. Optionally, the functions of storage sections  10 B and  10 D can be reversed, such that restructured data from storage sections  10 A and  10 C will be copied into storage section  10 D until storage section  10 D is restructured and transferred back onto storage section  10 B (target storage section). 
     In each data storage section the data is stored in a linear fashion, and subsequent data blocks are stored in subsequent areas of the data storage section. The wording “top to bottom” and “bottom to top” in the above described data storage method is used illustratively for any two clearly distinguishable and dividable storage allotments and formats. For example, data may be written from “left to right” or “right to left.” 
     For continuous high data rate information storage and retrieval, the method of the present invention for data storage and retrieval wherein two similar data storage sections  10  are provided requires that each storage section  10  is equipped with at least two parallel and independent read and write mechanisms. Similarly, for three or more similar data storage sections, the method for data storage and retrieval may be operated with one or more read and write mechanisms for each storage section. An increasing number of storage sections and number of read and write mechanisms for each section will lead to a higher degree of parallel processing and accelerate the data access and process speed. 
     The organization method for data storage and retrieval of the present invention enables the development of fundamentally new data storage devices, in which the mechanism of data storage does no longer require the reversal of individual bits. Data organized in a block method is written and retrieved with much higher speed. The slow process of deleting data is accomplished by reinitializing entire storage sections that are not immediately utilized to write data. The larger the storage capacity, the more beneficial this method is in comparison to conventional bit-by-bit methods. Using current state-of-the-art technology storage densities approaching 10 13  bits/inch 2  and data access times of 1 ns are possible. Considering that the size of each of the above described storage sections  10  is approximately 1 inch 2 , it will take 10000s, or nearly 3 hours, at full data rate of 1 GHz (Gigahertz) to fill one section. Thus, in a 24-hour period at a data rate of 1 GHz, no storage section  10  needs to be restructured and copied more than 4 times, while nearly 10 14  bits will have been stored. 
     In view of the above detailed description, various other modifications and variations will now become apparent to those skilled in the art. It is intended that the present invention of the appended claims cover all reasonable modifications and variations without departing from the spirit and scope of the invention. In particular, more than four storage sections may be employed and the process of writing and restructuring between storage sections may be varied, but remain within the scope of the appended claims.