Updateable centralized data position information storage system

1. A method of centralized data position information storage, comprising the steps of:

arranging a byte stream of data into partitioned logical data;

storing data position information relating to said logical data in an updateable centralized storage area;

utilizing said information to locate target data that is part of said logical data; and

storing said data position information in said storage area, said step of storing said data position information comprising:

applying a first store algorithm to said target data to update said storage area with target data position information; and

applying a second store algorithm to non-target data to update said storage area with non-target data position information.

2. The method as claimed in claim 1 , wherein:

said first and said second algorithms are operable to store said data position information in a data table; and

said data table is configurable to store data position information relating to said logical data, said logical data comprising records and filemarks.

3. The method as claimed in claim 1 wherein said step of utilizing said data position information comprises applying a search algorithm to said data position information, said search algorithm being configured to locate said target data.

4. A method of updating data position information on a tape storage device, said method comprising the steps of:

arranging a byte stream of data into partitioned logical data and recording said data onto a length of tape;

storing data position information relating to said logical data in an updateable centralized storage area;

determining a required transporting of said logical data past a read head by utilizing said information;

reading, from said tape with the read head, target data by using the determination required transporting, said tar- get data being part of said logical data;

updating said storage area with data position information obtained following transporting of said logical data past said read head, the step of updating said storage area comprising:

(a) reading said logical data on said tape by using said read head; said read head being configurable for said reading of said data in response to the velocity of said logical data being transported past said read head being below a predetermined value; and

(b) writing said data position information to said storage area;

the step of updating said storage area comprising:

(a) reading said target data on said tape using said read head;

(b) writing target data position information to said storage area; and

(c) transferring said data position information from a reserve storage area to said centralized storage area;

following said step of updating said centralized storage area, transferring said data position information from said centralized storage area to said reserve storage area, said updateable centralized storage area including no data position information prior to a first transporting of said logical data past said read head; and

storing said data position information in said centralized storage area following said first transporting of logical data.

5. A data position information storage and utilization device comprising:

a length of tape for storing partitioned logical data so the partitioned logical data is adapted to be distributed across the length of the tape;

an updateable centralized storage area for receiving and storing data position information relating to said logical data;

a search algorithm for locating target data that is part of said logical data;

a read head for reading said data from said tape, said information being adapted to be stored in said storage area following transporting of said logical data past said read head;

a first store algorithm for controlling the reading of target data from said tape and the storing of said target data position information in said storage area; and

a second store algorithm for controlling the reading of non-target data from said tape and the storing of non-target data position information in said storage area.

6. A device as claimed in claim 5 , wherein said updateable centralized storage area is configurable to store data position information relating to substantially all of said logical data.

7. A device as claimed in claim 5 wherein said updateable centralized storage area is configurable to store data position information relating to selected data groups, said data groups being adapted to be distributed across said length of tape.

8. A device as claimed in claim 5 , further comprising a tape drive, wherein said updateable centralized storage area, said read head, said search algorithm and said first and said second store algorithms are located in said tape drive.