Recording device, readout device, recording method, recording program, readout method, readout program, and magnetic tape

1. A recording device comprising:

a recording unit that records a plurality of objects on a portable recording medium, each of the plurality of objects including data and metadata related to the data, and executes a process of recording first set data, in addition to the plurality of objects and at every predetermined timing after recording at least one object of the plurality of objects, the first set data being a set of metadata included in the at least one object, and the predetermined timing corresponding to every time a total size of the plurality of objects that are recorded exceeds a predetermined size,

wherein, in a case in which there is already recorded first set data, each piece of first set data recorded thereafter is a set of metadata included in at least one object recorded after recording of an immediately preceding recorded piece of first set data.

2. The recording device according to claim 1 ,

wherein the recording unit records second set data, which is a set of at least one recorded first set data, on the portable recording medium, after recording at least one piece of the first set data, and

wherein, in a case in which there is already recorded second set data, each piece of the recorded second set data is a set of all first set data recorded between the piece of the second set data and an immediately preceding piece of second set data.

3. The recording device according to claim 2 ,

wherein the recording unit (i) determines whether a size of a piece of the second set data recorded on the portable recording medium is equal to or less than a predetermined size, and (ii) in a case in which the size of the piece of the second set data is equal to or less than a predetermined size, records a next object to be recorded and thereby overwrites the piece of second set data on the portable recording medium.

4. The recording device according to claim 2 ,

wherein the portable recording medium includes a reference partition and a data partition in which the object is recorded, and

wherein the recording unit (i) records the first set data and the second set data in the data partition, (ii) determines whether a size of a piece of the second set data recorded on the portable recording medium exceeds a predetermined size, and (iii) in a case where the size of the piece of the second set data recorded in the data partition exceeds the predetermined size, records the piece of the second set data recorded in the data partition in the reference partition.

5. The recording device according to claim 4 ,

wherein in a case where the second set data recorded in the data partition is recorded in the reference partition, the recording unit records the second set data recorded in the data partition in the reference partition without deleting the second set data.

6. The recording device according to claim 1 ,

wherein the metadata includes system-specific identification information and object-specific identification information including the metadata.

7. The recording device according to claim 1 ,

wherein the portable recording medium is a magnetic tape.

8. A recording method executed by a computer, the method comprising:

recording a plurality of objects on a portable recording medium, each of the plurality of objects including data and metadata related to the data; and

executing a process of recording first set data, in addition to the plurality of objects and at every predetermined timing after recording at least one object of the plurality of objects, the first set data being a set of metadata included in the at least one object, and the predetermined timing corresponding to every time a total size of recorded objects exceeds a predetermined size, wherein, in a case where there is already recorded first set data, each piece of first set data recorded thereafter is a set of metadata included in at least one object recorded after recording of an immediately preceding recorded piece of first set data.

9. A non-transitory storage medium storing a program for causing a computer to execute a recording processing, the recording processing comprising:

recording a plurality of objects on a portable recording medium, each of the plurality of objects including data and metadata related to the data; and

executing a process of recording first set data, in addition to the plurality of objects and at every predetermined timing after recording at least one object of the plurality of objects, the first set data being a set of metadata included in the at least one object, and the predetermined timing corresponding to every time a total size of recorded objects exceeds a predetermined size,

wherein, in a case where there is already recorded first set data, each piece of first set data recorded thereafter is a set of metadata included in at least one object recorded after recording of an immediately preceding recorded piece of first set data.

10. A process of recording a plurality of objects on a magnetic tape, each of the plurality of objects including data and metadata related to the data, the process comprising recording first set data, in addition to the plurality of objects, the first set data being a set of metadata included in at least one of the plurality of objects, each piece of first set data being at a position on the tape corresponding to every predetermined timing after at least one of the plurality of objects is recorded,

wherein, in a case in which there is already recorded first set data, each piece of first set data recorded thereafter is a set of metadata included in an object recorded immediately after recording of a preceding piece of first set data.

11. The process of recording claim 10 , further comprising additionally recording on the magnetic tape second set data, the second set data being a set of at least one recorded first set data on the portable recording medium, wherein, in a case where there is already recorded second set data, each piece of the second set data is a set of all first set data recorded between the piece of the second set data and an immediately preceding piece of second set data.