Commitment control for less than an entire record in an in-memory database in a parallel computer system

• US 8,027,996 B2
• Filed: 11/29/2007
• Issued: 09/27/2011
• Est. Priority Date: 11/29/2007
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Barsness, Eric Lawrence, Santosuosso, John Matthew, Peters, Amanda
• Primary Examiner(s): Wu; Yicun
• Assistant Examiner(s): Mamillapalli; Pavan
• Application Number:
  US11/947,009
• Publication Number:
  US 20090144337A1
• Time in Patent Office: 1,398 Days
• Field of Search: 707/200, 707/612, 707/613, 707/764, 707/790, 707/802, 707/999.202, 707/999.102, 707/792, 711/108
• US Class Current: 707/792
• CPC Class Codes: G06F 16/2379 Updates performed during online database operations; commit processing

Abstract

In a networked computer system that includes multiple interconnected nodes, a commitment control mechanism allows designating certain portions of a record in an in-memory database as mandatory and other portions of the record as secondary, and performs mandatory commitment control once all the mandatory portions are available even if one or more secondary portions are not yet available. The secondary portions may be under separate commitment control that is asynchronous to the commitment control for the mandatory portions, or may be under no commitment control at all. The result is a commitment control mechanism that performs commitment control for portions of a record that are marked mandatory even when one or more of the portions marked secondary are not available.

Claims

1. A parallel computer system comprising:

a plurality of nodes coupled together, each node including at least one processor and memory;

an in-memory database residing in the plurality of nodes, the in-memory database defining a record that includes at least one mandatory portion that must be present for a change to the record to commit and at least one secondary portion that need not be present for a change to the record to commit;

a database manager residing in a memory, the database manager comprising;

a mandatory commit mechanism that commits changes to the at least one mandatory portion of the record when all mandatory portions of the record are available during a transaction and when at least one secondary portion is not available.

2. The parallel computer system of claim 1 further comprising a secondary commit mechanism that functions asynchronously with respect to the mandatory commit mechanism, the secondary commit mechanism committing changes to the at least one secondary portion of the record when all secondary portions of the record are available during the transaction.

3. The parallel computer system of claim 2 wherein the secondary commit mechanism commits the changes to the at least one secondary portion of the record after the mandatory commit mechanism commits the changes to the at least one mandatory portion of the record.

4. The parallel computer system of claim 1 wherein each mandatory portion is defined on a column boundary in the record.

5. The parallel computer system of claim 1 wherein a first mandatory portion and a first secondary portion are defined in a same column in the record.

6. A computer-implemented method for commitment control for an in-memory database in a parallel computer system, the method comprising the steps of:

(A) defining at least one portion of a record in the in-memory database as mandatory that must be present for a change to the record to commit;

(B) defining at least one portion of the record as secondary that need not be present for a change to the record to commit;

(C) allocating portions of the record to a plurality of nodes in the parallel computer system;

(D) monitoring mandatory portions of the record during a transaction; and

(E) when all mandatory portions of the record are available during the transaction and at least one secondary portion is not available, committing changes to all mandatory portions of the record.

7. The method of claim 6 further comprising the steps of:

(F) committing changes to all secondary portions of the record when all secondary portions of the record are available during the transaction, wherein the committing changes to all secondary portions of the record is done in a commit cycle that is separate and asynchronous to the commit cycle for the mandatory portions of the record in step (E).

8. The method of claim 7 wherein the committing of changes to all secondary portions in step (F) is performed after the committing of changes to all mandatory portions in step (E).

9. The method of claim 6 wherein each mandatory portion is defined on a column boundary in the record.

10. The method of claim 6 wherein a first mandatory portion and a first secondary portion are defined in a same column in the record.

11. A method for deploying computing infrastructure, comprising integrating computer readable code into a computing system, wherein the code in combination with the computing system perform the method of claim 6.

12. A computer-implemented method for commitment control for an in-memory database in a parallel computer system, the method comprising the steps of:

(A) marking at least one portion of a record in the in-memory database as mandatory that must be present for a change to the record to commit;

(B) marking at least one portion of the record as secondary that need not be present for a change to the record to commit;

(C) allocating portions of the record to a plurality of nodes in the parallel computer system;

(D) starting a transaction to the record in the in-memory database;

(E) monitoring all mandatory portions of the record during the transaction;

(F) when all mandatory portions of the record are available during the transaction and at least one secondary portion is not available and the transaction has not timed out, committing changes to the mandatory portions of the record;

(G) after performing step (F), committing changes to all secondary portions of the record when all secondary portions of the record are available during the transaction and the transaction has not timed out, wherein the committing changes to all secondary portions of the record is done in a commit cycle that is separate and asynchronous to the commit cycle for the mandatory portions of the record in step (F).

13. The method of claim 12 wherein each mandatory portion is defined on a column boundary in the record.

14. The method of claim 12 wherein a first mandatory portion and a first secondary portion are defined in a same column in the record.

15. A computer-readable article of manufacture comprising:

a database manager comprising a mandatory commit mechanism that monitors during a transaction a record that includes at least one mandatory portion that must be present for a change to the record to commit and at least one secondary portion that need not be present for a change to the record to commit, the database manager committing changes to at least one mandatory portion of the record when all mandatory portions of the record are available during the transaction and when at least one secondary portion is not available; and

recordable media bearing the database manager.

16. The article of manufacture of claim 15 wherein the database manager further comprises a secondary commit mechanism that functions asynchronously with respect to the mandatory commit mechanism, the secondary commit mechanism committing changes to the at least one secondary portion of the record when all secondary portions of the record are available during the transaction.

17. The article of manufacture of claim 16 wherein the secondary commit mechanism commits the changes to the at least one secondary portion of the record after the mandatory commit mechanism commits the changes to the at least one mandatory portion of the record.

18. The article of manufacture of claim 15 wherein each mandatory portion is defined on a column boundary in the record.

19. The article of manufacture of claim 15 wherein a first mandatory portion and a first secondary portion are defined in a same column in the record.