Data Corruption Diagnostic Engine

• US 20090106603A1
• Filed: 10/17/2008
• Published: 04/23/2009
• Est. Priority Date: 10/19/2007
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Sun, Hubert Ken, Susairai, Margaret, Hu, Wei-Ming, Dilman, Mark, Stewart, Michael James, Kuchibhotla, Balasubrahmanyam
• Granted Patent: US 8,074,103 B2
• Time in Patent Office: Days
• US Class Current: 714/42
• CPC Class Codes: G06F 11/0727 in a storage system, e.g. in a DASD or network based storage system drivers for digital recording or reproducing units G06F3/06; circuits for error detection or correction within digital recording or reproducing units G11B20/18; for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS], H04L67/1097
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 11/327 Alarm or error message display

Abstract

A computer is programmed to execute a diagnostic procedure either on a pre-set schedule or asynchronously in response to an event, such as an error message, or a user command. When executed, the diagnostic procedure automatically checks for integrity of one or more portions of data in the computer, to identify any failure(s). In some embodiments, the failure(s) may be displayed to a human, after revalidation to exclude any failure that no longer exists.

Claims

1. A computer-implemented method to process errors related to a data storage system, said errors arising from a plurality of storage structures in said data storage system, the method comprising:

checking integrity of data in a storage structure from which an error arises;

wherein a failure, if existing in said storage structure, is identified by said checking; and

storing in a memory, a set of failures, said set comprising said failure and additional failures;

wherein said additional failures, if existing in said storage structure, are identified by at least one of;

(a) said checking and (b) repeating said checking.

2. The method of claim 1 wherein:

said checking is performed by execution of a diagnostic procedure;

said diagnostic procedure is identified by use of at least said error.

3. The method of claim 2 wherein:

the diagnostic procedure, when executed, verifies correctness of at least one value in at least one storage structure in the data storage system, to automatically identify a failure that caused the error.

4. The method of claim 1 wherein:

the diagnostic procedure is automatically selected by the computer, from among a plurality of predetermined diagnostic procedures;

each error in the plurality of predetermined errors is associated in said memory to at least one diagnostic procedure in the plurality of predetermined diagnostic procedures;

5. The method of claim 1 wherein:

said checking is performed in response at least partially to occurrence of said error during said system accessing said data.

6. The method of claim 1 wherein said error is hereinafter “

first error”

, the method further comprising;

prior to said checking integrity, determining whether a second error identical to said first error had occurred within a predetermined duration prior to said first error; and

performing said checking integrity only if a result of said determining is false.

7. The method of claim 1 wherein said failure is hereinafter “

first failure”

, each failure has an type and each failure has at least one parameter, the method further comprising;

prior to said storing, additionally checking whether a second failure among said additional failures is of same type as said first failure; and

creating a third failure with a third value for said parameter based on a first value of the first failure and a second value of the second failure;

wherein said third failure is included in said set during said storing;

wherein said third failure is identified in said memory as a parent of the first failure and the second failure.

8. The method of claim 1 wherein:

said failure is hereinafter “

first failure” and

said storage structure is hereinafter “

first storage structure” and

said first failure has a type;

an additional failure is hereinafter “

second failure” and

said second failure is of said type;

said second failure is related to a second storage structure in said plurality of storage structures;

said first storage structure and said second storage structure are comprised in a third storage structure in said plurality of storage structures; and

the method further comprises creating a third failure based at least partially on information related to said first failure and said second failure.

9. The method of claim 1 further comprising:

determining, for each failure in the set of failures, an attribute indicative of impact of said each failure; and

storing in said memory, said attribute for said each failure.

10. The method of claim 1 wherein:

each error is associated, by a table outside said plurality of storage structures, with at least one procedure in a plurality of predetermined procedures, each procedure verifying correctness of at least one value in one of said plurality of storage structures.

11. The method of claim 1 wherein said storing comprises saving to said memory, associated with each failure, at least:

priority of the failure;

a time of creation of said each failure;

a status of said each failure selected from a group consisting of (open and closed); and

an identifier of software to revalidate said each failure.

12. The method of claim 1 further comprising:

revalidating each failure in said set of failures; and

mark said each failure as closed if said revalidating finds said each failure no longer exists in said computer.

13. The method of claim 1 wherein:

said storage structure comprises a file;

said checking verifies no corruption in at least a header of said file, followed by use of at least a portion of information in the file to verify no corruption or loss of a second storage structure.

14. The method of claim 1 wherein:

said system comprises a database management system; and

said storage structure comprises a data block of a database accessible via said database management system.

15. A computer-readable storage medium comprising instructions to process a plurality of errors related to a data storage system, said data storage system comprising a plurality of storage structures, each storage structure comprising data stored persistently in non-volatile storage media of the data storage system, the computer-readable storage medium comprising:

instructions responsive at least partially to occurrence of a first error in said plurality of errors, to check integrity of data in a storage structure from which said first error arises, thereby to identify a failure of said storage structure;

instructions to store in a memory, a set of failures, said set comprising said failure and additional failures.

16. The computer-readable storage medium of claim 15 further comprising:

instructions to determine whether a second error identical to said first error occurred within a predetermined duration prior to said first error, and only if a result thereof is false invoke performance of said instructions to check integrity.

17. The computer-readable storage medium of claim 15 further comprising:

instructions to identify said instructions to check integrity, by use of at least said error.

18. The computer-readable storage medium of claim 15 wherein:

said instructions to check integrity comprise instructions to verify correctness of a value in at least a portion of the storage structure, to automatically identify said failure that caused the first error.

19. The computer-readable storage medium of claim 15 further comprising:

instructions to determine, for each failure in the set of failures, an attribute indicative of impact of said each failure; and

instructions to store in said memory, said attribute for said each failure.

20. The computer-readable storage medium of claim 15 further comprising:

instructions to store in said memory a priority of the failure;

instructions to store in said memory a time of creation of said each failure; and

instructions to store in said memory, an identifier of software to revalidate said each failure.

21. A database management system, implemented at least partially by a computer, to correct a plurality of predetermined errors that corrupt data in a database in the computer, the database management system comprising:

means responsive at least partially to occurrence of said first error during said system accessing said data, for checking integrity of data in a storage structure from which a first error arises, thereby to identify a failure of said storage structure;

means for storing in a memory, a set of failures, said set comprising said failure and additional failures.