SYSTEM AND METHOD FOR UTILIZING GENERATIONAL FILE NAMES FOR DIAGNOSTIC DATA FILES

• US 20090216817A1
• Filed: 02/26/2008
• Published: 08/27/2009
• Est. Priority Date: 02/26/2008
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Partridge, Ian O., Normington, Glyn
• Granted Patent: US 7,991,793 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/164 File meta data generation

Abstract

A system and associated method for utilizing file names for diagnostic data files generated by a runtime environment. The method employs a file counter base that defines a predefined maximum number of files permitted in a file system, a generation number that indicates an instance of the runtime environment, and a file counter that comprises a file name. The file counter circulates by a cycle equal to the file counter base such that the file system uses only a limited disk space. The method determines the generation number per instance of the runtime environment by examining file counters of existing files in the file system. The generation number initializes the file counter for creating file names in the instance of the runtime environment. The method guarantees a longest life span of a diagnostic data file in a file system that has a limited number of files.

Claims

1. A method for utilizing file names, the method comprising:

initializing a generation number (Z) such that a number of files in a file system does not exceed a predetermined maximum number of files permitted in the file system and such that each file in the file system stays for a longest life span before being overwritten, wherein said initializing is performed at startup of a runtime environment that manipulates the file system, wherein a file counter base (X) defines the predetermined maximum number of files permitted in the file system, wherein each file in the file system is uniquely identified by a respective file name (N) that comprises a respective file counter (F);

subsequent to said initializing, setting a file counter (F) to the generation number (Z);

subsequent to said setting, storing a file in the file system by a file name (N) comprising the file counter (F); and

subsequent to said storing, recalculating a new value of the file counter (F) from a current value of the file counter (F).

2. The method of claim 1, said initializing comprising:

locating, in the file system, a smallest value of the file counter (F) that is not used in all file names for existing files in the file system;

subsequent to said locating, determining that the smallest value of the file counter (F) from said locating is less than the file counter base (X); and

responsive to said determining, assigning the smallest value of the file counter (F) from said locating to the generation number (Z).

3. The method of claim 1, said initializing comprising:

locating, in the file system, a smallest value of the file counter (F) that is not used in all file names for existing files in the file system;

subsequent to said locating, determining that the smallest value of the file counter (F) from said locating is equal to the file counter base (X); and

responsive to said determining, assigning zero (0) to the generation number (Z).

4. The method of claim 1, said recalculating comprising:

assigning a value resulting from a mathematical modulo operation on the current value of the file counter (F) incremented by one (1) and the file counter base (X), that is ((F+1) MOD X), to the new value of the file counter (F).

5. The method of claim 1, the method further comprising:

subsequent to said recalculating, re-performing said storing and said recalculating, responsive to determining that a new file needs to be stored in the file system, wherein the runtime environment runs continuously after said initializing.

6. The method of claim 1, wherein the file name (N) further comprises a file name pattern (Y) that defines how to form the file name (N).

7. The method of claim 1, wherein the file name (N) further comprises a member of the group consisting of a process identifier and a timestamp.

8. A computer program product, comprising a computer usable storage medium having a computer readable program code embodied therein, said computer readable program code containing instructions that when executed by a processor of a computer system implement a method for utilizing file names, the method comprising:

initializing a generation number (Z) such that a number of files in a file system does not exceed a predetermined maximum number of files permitted in the file system and such that each file in the file system stays for a longest life span before being overwritten, wherein said initializing is performed at startup of a runtime environment that manipulates the file system, wherein a file counter base (X) defines the predetermined maximum number of files permitted in the file system, wherein each file in the file system is uniquely identified by a respective file name (N) that comprises a respective file counter (F);

subsequent to said initializing, setting a file counter (F) to the generation number (Z);

subsequent to said setting, storing a file in the file system by a file name (N) comprising the file counter (F); and

subsequent to said storing, recalculating a new value of the file counter (F) from a current value of the file counter (F).

9. The computer program product of claim 8, said initializing comprising:

locating, in the file system, a smallest value of the file counter (F) that is not used in all file names for existing files in the file system;

subsequent to said locating, determining that the smallest value of the file counter (F) from said locating is less than the file counter base (X); and

responsive to said determining, assigning the smallest value of the file counter (F) from said locating to the generation number (Z).

10. The computer program product of claim 8, said initializing comprising:

locating, in the file system, a smallest value of the file counter (F) that is not used in all file names for existing files in the file system;

subsequent to said locating, determining that the smallest value of the file counter (F) from said locating is equal to the file counter base (X); and

responsive to said determining, assigning zero (0) to the generation number (Z).

11. The computer program product of claim 8, said recalculating comprising:

assigning a value resulting from a mathematical modulo operation on the current value of the file counter (F) incremented by one (1) and the file counter base (X), that is ((F+1) MOD X), to the new value of the file counter (F).

12. The computer program product of claim 8, the method further comprising:

subsequent to said recalculating, re-performing said storing and said recalculating, responsive to determining that a new file needs to be stored in the file system, wherein the runtime environment runs continuously after said initializing.

13. The computer program product of claim 8, wherein the file name (N) further comprises a file name pattern (Y) that defines how to form the file name (N).

14. The computer program product of claim 8, wherein the file name (N) further comprises a member of the group consisting of a process identifier and a timestamp.

15. A computer system comprising a processor and a computer readable memory unit coupled to the processor, said memory unit containing instructions that when executed by the processor implement a method for utilizing file names, the method comprising:

initializing a generation number (Z) such that a number of files in a file system does not exceed a predetermined maximum number of files permitted in the file system and such that each file in the file system stays for a longest life span before being overwritten, wherein said initializing is performed at startup of a runtime environment that manipulates the file system, wherein a file counter base (X) defines the predetermined maximum number of files permitted in the file system, wherein each file in the file system is uniquely identified by a respective file name (N) that comprises a respective file counter (F);

subsequent to said initializing, setting a file counter (F) to the generation number (Z);

subsequent to said setting, storing a file in the file system by a file name (N) comprising the file counter (F); and

subsequent to said storing, recalculating a new value of the file counter (F) from a current value of the file counter (F).

16. The computer system of claim 15, said initializing comprising:

locating, in the file system, a smallest value of the file counter (F) that is not used in all file names for existing files in the file system;

subsequent to said locating, determining that the smallest value of the file counter (F) from said locating is less than the file counter base (X); and

responsive to said determining, assigning the smallest value of the file counter (F) from said locating to the generation number (Z).

17. The computer system of claim 15, said initializing comprising:

locating, in the file system, a smallest value of the file counter (F) that is not used in all file names for existing files in the file system;

subsequent to said locating, determining that the smallest value of the file counter (F) from said locating is equal to the file counter base (X); and

responsive to said determining, assigning zero (0) to the generation number (Z).

18. The computer system of claim 15, said recalculating comprising:

assigning a value resulting from a mathematical modulo operation on the current value of the file counter (F) incremented by one (1) and the file counter base (X), that is ((F+1) MOD X), to the new value of the file counter (F).

19. The computer system of claim 15, the method further comprising:

subsequent to said recalculating, re-performing said storing and said recalculating, responsive to determining that a new file needs to be stored in the file system, wherein the runtime environment runs continuously after said initializing.

20. The computer system of claim 15, wherein the file name (N) further comprises a file name pattern (Y) that defines how to form the file name (N).