Timing index writes to a tape medium

• US 10,242,707 B1
• Filed: 06/13/2018
• Issued: 03/26/2019
• Est. Priority Date: 06/13/2018
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Hasegawa, Tohru, Itagaki, Hiroshi, Miyamura, Tsuyoshi, Matsui, Sosuke, Mitsuma, Shinsuke, Yamamoto, Noriko
• Primary Examiner(s): Hindi, Nabil Z
• Application Number:
  US16/007,074
• Time in Patent Office: 286 Days
• CPC Class Codes: G11B 20/10222 clock-related aspects, e.g. phase or frequency adjustment or bit synchronisation dedicated sync patterns in the modulation code G11B20/1403
• CPC Class Codes: G11B 20/1201 on tapes
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: G11B 5/00813 magnetic tapes

Abstract

Aspects of the present disclosure relate to a method for timing index write to a tape medium of a tape system. Index write timing data that specifies index write timing based on file metadata attributes is stored. Metadata attributes of a first file are analyzed to determine whether a first index should be written at a first time based on the index write timing data. In response to determining that an index should be written, the first index is written to the tape medium at the first time.

Claims

1. A method for timing index writes to a tape medium of a tape system, the method comprising:

storing index write timing data that specifies index write timing based on file metadata attributes;

analyzing metadata attributes of a first file to determine whether a first index should be written at a first time based on the index write timing data; and

writing, in response to determining that the first index should be written, the first index to the tape medium at the first time.

2. The method of claim 1, wherein the index write timing data specifies that indices are required to be written upon file closure for any file having a first file attribute, wherein analyzing metadata attributes associated with the first file includes determining that the first file includes the first file attribute, wherein the first time corresponds to a time of file closure of the first file, wherein the first index is written at the first time based on the file having the first attribute.

3. The method of claim 1, further comprising:

analyzing metadata of a second file to determine that the second file is of a second file format, wherein the index write timing data specifies that indices are not to be written upon file closure for any file having the second file format;

determining whether to write a second index at a second time, wherein the second time corresponds to a time of file closure of the second file; and

not writing the second index based on the second file being of the second file format and the second time being the time of file closure of the second file.

4. The method of claim 1, wherein the index write timing data specifies that indices are not to be written while any file having a first file attribute is open, wherein analyzing metadata associated with the first file includes determining that the file does not have the first file attribute, wherein the first time corresponds to a time of a periodic index write operation, wherein the first index is written at the first time based on the file not having the first file attribute.

5. The method of claim 1, further comprising:

analyzing metadata of a second file to determine that the second file has a second file attribute, wherein the index write timing data specifies that indices are permitted to be written while any file having the second file attribute is open;

determining whether to write a second index at a second time, wherein the second time corresponds to a time of a periodic index write; and

writing the second index at the second time based on the second file having the second file attribute and the second time being the time of the periodic index write.

6. The method of claim 1, wherein the index write timing data is stored in a configuration file in non-volatile memory located on the tape system.

7. The method of claim 1, wherein the first index is written adjacent to the first file in a data partition of the tape medium, wherein the first index is additionally written to an index partition of the tape medium.

8. A system comprising:

a tape system having a tape medium; and

a processor configured to perform a method for timing index writes to the tape medium of the tape system, the method comprising;

storing index write timing data that specifies index write timing based on file metadata attributes;

analyzing metadata attributes of a first file to determine whether a first index should be written at a first time based on the index write timing data; and

writing, in response to determining that the first index should be written, the first index to the tape medium at the first time.

9. The system of claim 8, wherein the index write timing data specifies that indices are to be written upon file closure for any file having a first file attribute, wherein analyzing metadata associated with the first file includes determining that the first file includes the first file attribute, wherein the first time corresponds to a time of file closure of the first file, wherein the first index is written at the first time based on the file having the first file attribute.

10. The system of claim 8, wherein the method performed by the process further comprises:

analyzing metadata of a second file to determine that the second file is of a second file format, wherein the index write timing data specifies that indices are not to be written upon file closure for any file having the second file format;

determining whether to write a second index at a second time, wherein the second time corresponds to a time of file closure of the second file; and

not writing the second index at the second time based on the second file being of the second file format and the second time being the time of file closure of the second file.

11. The system of claim 8, wherein the index write timing data specifies that indices are not to be written while any file having a first file attribute is open, wherein analyzing metadata associated with the first file includes determining that the file does not include the first file attribute, wherein the first time corresponds to a time of a periodic index write, wherein the first index is written at the first time based on the first file not including the first file attribute.

12. The system of claim 8, wherein the method performed by the processor further comprises:

analyzing metadata of a second file to determine that the second file is of a second file format, wherein the index write timing data specifies that indices are permitted to be written while any file having the second file format is open;

determining whether to write a second index at a second time, wherein the second time corresponds to a time of a periodic index write; and

writing the second index at the second time based on the second file being of the second file format and the second time being the time of the periodic index write.

13. The system of claim 8, wherein the index write timing data is stored in a configuration file in non-volatile memory located on a computer system including the processor.

14. The system of claim 8, wherein the first index is written adjacent to the first file in a data partition of the tape medium, wherein the first index is additionally written to an index partition of the tape medium.

15. A computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a processor to cause the processor to perform a method for timing index writes to a tape medium of a tape system, the method comprising:

storing index write timing data that specifies index write timing based on file metadata attributes;

analyzing metadata attributes of a first file to determine whether a first index should be written at a first time based on the index write timing data; and

writing, in response to determining that the first index should be written, the first index to the tape medium at the first time.

16. The computer program product of claim 15, wherein the index write timing data specifies that indices are required to be written upon file closure for any file having a first file attribute, wherein analyzing metadata attributes associated with the first file includes determining that the first file includes the first file attribute, wherein the first time corresponds to a time of file closure of the first file, wherein the first index is written at the first time based on the file having the first attribute.

17. The computer program product of claim 15, wherein the method performed by the processor further comprises:

analyzing metadata of a second file to determine that the second file is of a second file format, wherein the index write timing data specifies that indices are not to be written upon file closure for any file having the second file format;

determining whether to write a second index at a second time, wherein the second time corresponds to a time of file closure of the second file; and

not writing the second index based on the second file being of the second file format and the second time being the time of file closure of the second file.

18. The computer program product of claim 15, wherein the index write timing data specifies that indices are not to be written while any file having a first file attribute is open, wherein analyzing metadata associated with the first file includes determining that the file does not have the first file attribute, wherein the first time corresponds to a time of a periodic index write operation, wherein the first index is written at the first time based on the file not having the first file attribute.

19. The computer program product of claim 15, wherein the method performed by the processor further comprises:

analyzing metadata of a second file to determine that the second file has a second file attribute, wherein the index write timing data specifies that indices are permitted to be written while any file having the second file attribute is open;

determining whether to write a second index at a second time, wherein the second time corresponds to a time of a periodic index write; and

writing the second index at the second time based on the second file having the second file attribute and the second time being the time of the periodic index write.

20. The computer program product of claim 15, wherein the index write timing data is stored in a configuration file in cartridge memory located on the tape system.