HIGH SPEED DATA HISTORIAN

• US 20080215641A1
• Filed: 03/01/2007
• Published: 09/04/2008
• Est. Priority Date: 03/01/2007
• Status: Active Grant

• Current Assignee: Air Liquide Large Industries U S LP (L'Air Liquide SA)
• Original Assignee: Air Liquide Large Industries U S LP (L'Air Liquide SA)
• Inventors: Mukhi, Sultan Q.
• Granted Patent: US 7,853,568 B2
• Time in Patent Office: Days
• US Class Current: 707/204
• CPC Class Codes: G05B 21/02 electric
• CPC Class Codes: G05B 23/0264 Control of logging system, e.g. decision on which data to store; time-stamping measurements

Abstract

Techniques for operating an archival database, referred to as a historian, are disclosed. The historian may be used to archive values from a real-time database. Data values to be archived in the historian are first written to a short-term, high-availability repository, such as a memory-mapped database. As data values “fill” the short-term repository, an archival processor application may be configured to “drain” them from the short-term repository and store them in a high-capacity, long-term archive, such as a disk-based database. Thus, the short-term repository may be used to provide fast access to the recent operational history of a monitored system, (e.g., a complex pipeline network), where long-term archive may be used to provide access to a comprehensive operational history of the monitored system.

Claims

1. A method of archiving a plurality of data values from a real-time database in a historian database, wherein the historian database includes a short-term repository and a long-term archive, comprising:

obtaining one of the plurality of data values from the real-time database, wherein the real-time database is configured to monitor a current operational state of an industrial system, wherein the plurality of data values correspond to information reflecting an operational state of one or more monitored devices of the industrial system, and wherein the obtained data value is stored in a tag that includes a timestamp and a tag ID identifying a monitored parameter in the real-time database;

evaluating the tag to determine whether to store the tag in the historian database;

upon determining to store the tag in the historian database, storing the tag in the short-term repository;

evaluating a set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive; and

upon determining to store one or more of the set of tags in the long-term archive, copying the tag from the short-term repository to the long-term archive and removing the tag from the short-term repository.

2. The method of claim 1, wherein the short-term repository is a memory-mapped database.

3. The method of claim 1, wherein the long-term archive is a disk-based database.

4. The method of claim 1, wherein obtaining one of the plurality of data values from the real-time database comprises periodically retrieving a then current value of the data value from the real-time database.

5. The method of claim 1, wherein obtaining one of the plurality of data values from the real-time database comprises receiving a precious value of the data value, after the data value has changed by a predetermined amount in the real-time database.

6. The method of claim 1, further comprising, copying the one or more tags copied from the short-term repository to the long-term archive to a backup database.

7. The method of claim 1, wherein evaluating the set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive comprises determining whether any of the set of tags have been in the short-term repository for a pre-determined time period.

8. The method of claim 1, wherein evaluating the set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive comprises, determining whether the short-term repository has a maximum number of tags of a given type.

9. The method of claim 1, further comprising:

monitoring the rate at which data values are obtained by the historian database;

upon determining that the rate at which data values exceeds a rate at which the historian database can process the data values;

writing the data values to an overflow file.

10. The method of claim 1, further comprising:

monitoring a number of tags of a given type in the short-term repository; and

upon determining that the number of tags of the given type in the short term repository exceeds an allocated number of tags of the given type, writing any obtained tags of the given type into an overflow file.

11. A computer-readable storage medium containing a program for archiving a plurality of data values from a real-time database in a historian database, the program including instructions for performing an operation, comprising:

obtaining one of the plurality of data values from the real-time database, wherein the real-time database is configured to monitor a current operational state of an industrial system, wherein the plurality of data values correspond to information reflecting an operational state of one or more monitored devices of the industrial system, and wherein the obtained data value is stored in a tag that includes a timestamp and a tag ID identifying a monitored parameter in the real-time database;

evaluating the tag to determine whether to store the tag in the historian database;

upon determining to store the tag in the historian database, storing the tag in the short-term repository;

evaluating a set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive; and

upon determining to store one or more of the set of tags in the long-term archive, copying the tag from the short-term repository to the long-term archive and removing the tag from the short-term repository.

12. The computer-readable storage medium of claim 11, wherein the short-term repository is a memory-mapped database.

13. The computer-readable storage medium of claim 11, wherein the long-term archive is a disk-based database.

14. The computer-readable storage medium of claim 11, wherein obtaining one of the plurality of data values from the real-time database comprises periodically retrieving a then current value of the data value from the real-time database.

15. The computer-readable storage medium of claim 11, wherein obtaining one of the plurality of data values from the real-time database comprises receiving a precious value of the data value, after the data value has changed by a predetermined amount in the real-time database.

16. The computer-readable storage medium of claim 11, wherein the operation further comprises, copying the one or more tags copied from the short-term repository to the long-term archive to a backup database.

17. The computer-readable storage medium of claim 11, wherein evaluating the set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive comprises determining whether any of the set of tags have been in the short-term repository for a pre-determined time period.

18. The computer-readable storage medium of claim 11, wherein evaluating the set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive comprises, determining whether the short-term repository has a maximum number of tags of a given type.

19. The computer-readable storage medium of claim 11, wherein the operations further comprise:

monitoring the rate at which data values are obtained by the historian database;

upon determining that the rate at which data values exceeds a rate at which the historian database can process the data values;

writing the data values to an overflow file.

20. The computer-readable storage medium of claim 11, wherein the operations further comprise:

monitoring a number of tags of a given type in the short-term repository; and

upon determining that the number of tags of the given type in the short term repository exceeds an allocated number of tags of the given type, writing any obtained tags of the given type into an overflow file.

21. A system archiving a plurality of data values from a real-time database in a historian database, comprising:

the real-time database, wherein the real-time database is configured to store a current value for the plurality of monitored data values, and wherein each of the plurality of data values correspond to information reflecting an operational parameter of one or more monitored devices of an industrial system;

the historian database, wherein the historian database includes a short-term repository and a long term archive, and wherein the historian database is configured to;

obtain one of the plurality of data values from the real-time database, wherein the obtained data value is stored in a tag that includes a timestamp and a tag ID identifying a monitored parameter in the real-time database,

evaluate the tag to determine whether to store the tag in the historian database,

upon determining to store the tag in the historian database, store the tag in the short-term repository,

evaluate a set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive, and

upon determining to store one or more of the set of tags in the long-term archive, copy the tag from the short-term repository to the long-term archive and removing the tag from the short-term repository.

22. The system of claim 21, wherein the short-term repository is a memory mapped database.

23. The system of claim 21, wherein the long-term archive is a disk-based database.

24. The system of claim 21, wherein the historian database is further configured to obtain one of the plurality of data values from the real-time database by periodically retrieving a then current value of the data value from the real-time database.

25. The system of claim 21, wherein the historian database is further configured to obtain one of the plurality of data values from the real-time database by receiving a precious value of the data value, after the data value has changed by a predetermined amount in the real-time database.

26. The system of claim 21, wherein the historian database is further configured to copy the one or more tags copied from the short-term repository to the long-term archive to a backup database.

27. The system of claim 21, wherein the historian database is configured to evaluate the set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive by determining whether any of the set of tags have been in the short-term repository for a predetermined time period.

28. The system of claim 21, wherein the historian database is configured to evaluate a set of tags in the short-term repository to determine whether to store any of the set of tags in the long-term archive by determining whether the short-term repository has a maximum number of tags of a given type.

29. The system of claim 21, wherein the historian is further configured to:

monitor the rate at which data values are obtained by the historian database; and

upon determining that the rate at which data values exceeds a rate at which the historian database can process the data values;

to write the data values to an overflow file.

30. The system of claim 21, wherein the historian database is further configured to:

monitor a number of tags of a given type in the short-term repository; and

upon determining that the number of tags of the given type in the short term repository exceeds an allocated number of tags of the given type, to write any obtained tags of the given type into an overflow file.