Transactional quality of service in event stream processing middleware

• US 8,103,714 B2
• Filed: 08/15/2008
• Issued: 01/24/2012
• Est. Priority Date: 08/15/2008
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Dorai, Chitra, Strom, Robert E.
• Primary Examiner(s): Swearingen, Jeffrey R
• Application Number:
  US12/192,876
• Publication Number:
  US 20100042999A1
• Time in Patent Office: 1,257 Days
• Field of Search: None
• US Class Current: 709/201
• CPC Class Codes: G06F 9/466 Transaction processing

Abstract

Computer implemented method, system and computer usable program code for achieving transactional quality of service in a transactional object store system. A transaction is received from a client and is executed, wherein the transaction comprises reading a read-only derived object, or reading or writing another object, and ends with a decision to request committing the transaction or a decision to request aborting the transaction. Responsive to a decision to request committing the transaction, wherein the transaction comprises writing a publishing object, events are delivered to event stream processing queries, and are executed in parallel with executing of the transaction. Responsive to a decision to request committing a transaction that comprises reading a read-only derived object, a validation is performed to determine whether the transaction can proceed to be committed, whether the transaction should abort, or whether the validation should delay waiting for one or more event stream processing queries to complete.

Claims

1. A computer-implemented method for achieving transactional quality of service in a transactional object store system having at least one client issuing transaction requests, at least one publishing object, at least one read-only derived object, and at least one event stream processing query, wherein a change to the at least one publishing object defines an event to be delivered to one or more of the at least one event stream processing query, wherein a state of the at least one read-only derived object represents a result of an event stream processing query, and wherein the at least one event stream processing query repeatedly receives an event from one or more of the at least one publishing object, determines a result based on a history of events from the one or more publishing object, and delivers the result to a read-only derived object of the at least one read-only derived object, the computer-implemented method comprising:

receiving a transaction from a client of the at least one client;

executing the transaction, wherein the transaction comprises one of reading a read-only derived object of the at least one read-only derived object, reading another object or writing another object, and wherein the transaction ends with one of a decision to request committing the transaction or a decision to request aborting the transaction;

responsive to a decision to request committing the transaction, wherein the transaction comprises writing one of the at least one publishing object, delivering events to event stream processing queries, and executing the delivered event stream processing queries in parallel with the executing of the transaction; and

responsive to a decision to request committing a transaction that comprises reading one of the at least one read-only derived object, performing a validation to determine whether the transaction can proceed to be committed, whether the transaction should abort, or whether the validation should delay waiting for one or more event stream processing queries to complete,

wherein if a first transaction updates a publishing object that triggers an event processing query that updates a derived object, any second transaction occurring logically later must see the updated value of the derived object.

2. The computer-implemented method of claim 1, further comprising:

assigning a tentative logical time to the transaction;

remembering latest read and write times for objects recently read and written; and

using the tentative logical time to determine whether it is necessary to perform one of;

adjusting the tentative logical time;

entering an optimistic state wherein the transaction is valid only if the validation succeeds; and

aborting the transaction.

3. The computer-implemented method of claim 2, wherein the validation succeeds if a particular derived object does not change in a particular range of logical times.

4. The computer-implemented method of claim 3, wherein the transaction is aborted if the particular derived object changes in the particular range of logical times.

5. The computer-implemented method of claim 1, wherein the transaction comprises a reading operation, and wherein the tentative logical time is adjusted according to whether a latest operation on the object was a read operation or a write operation.

6. The computer-implemented method of claim 1, wherein the transaction comprises a writing operation, and wherein the tentative logical time is adjusted according to a time of a latest read or write operation.

7. The computer-implemented method of claim 1, wherein the transactional object store system comprises an ObjectGrid transactional system.

8. A computer program product stored in a non-transitory computer usable device having computer usable program code embodied therein for achieving transactional quality of service in a transactional object store system having at least one client issuing transaction requests, at least one publishing object, at least one read-only derived object, and at least one event stream processing query, wherein a change to the at least one publishing object defines an event to be delivered to one or more of the at least one event stream processing query, wherein a state of the at least one read-only derived object represents a result of an event stream processing query, and wherein the at least one event stream processing query repeatedly receives an event from one or more of the at least one publishing object, determines a result based on a history of events from the one or more publishing object, and delivers the result to a read-only derived object of the at least one read-only derived object, the computer program product comprising:

computer usable program code configured for receiving a transaction from a client of the at least one client;

computer usable program code configured for executing the transaction, wherein the transaction comprises one of reading a read-only derived object of the at least one read-only derived object, reading another object or writing another object, and wherein the transaction ends with one of a decision to request committing the transaction or a decision to request aborting the transaction;

responsive to a decision to request committing the transaction, wherein the transaction comprises writing one of the at least one publishing object, computer usable program code configured for delivering events to event stream processing queries, and for executing the delivered event stream processing queries in parallel with the executing of the transaction; and

responsive to a decision to request committing a transaction that comprises reading one of the at least one read-only derived object, computer usable program code configured for performing a validation to determine whether the transaction can proceed to be committed, whether the transaction should abort, or whether the validation should delay waiting for one or more event stream processing queries to complete,

wherein if a first transaction updates a publishing object that triggers an event processing query that updates a derived object, any second transaction occurring logically later must see the updated value of the derived object.

9. The computer program of claim 8, further comprising:

computer usable program code configured for assigning a tentative logical time to the transaction;

computer usable program code configured for remembering latest read and write times for objects recently read and written; and

computer usable program code configured for using the tentative logical time to determine whether it is necessary to perform one of;

adjusting the tentative logical time;

entering an optimistic state wherein the transaction is valid only if the validation succeeds; and

aborting the transaction.

10. The computer program product of claim 9, wherein the validation succeeds if a particular derived object does not change in a particular range of logical times.

11. The computer program product of claim 10, wherein the transaction is aborted if the particular derived object changes in the particular range of logical times.

12. The computer program product of claim 8, wherein the transaction comprises a reading operation, and wherein the tentative logical time is adjusted according to whether a latest operation on the object was a read operation or a write operation.

13. The computer program product of claim 8, wherein the transaction comprises a writing operation, and wherein the tentative logical time is adjusted according to a time of a latest read or write operation.

14. A transactional object store system for achieving transactional quality of service in a transactional object store system having at least one client issuing transaction requests, at least one publishing object, at least one read-only derived object, and at least one event stream processing query, wherein a change to the at least one publishing object defines an event to be delivered to one or more of the at least one event stream processing query, wherein a state of the at least one read-only derived object represents a result of an event stream processing query, and wherein the at least one event stream processing query repeatedly receives an event from one or more of the at least one publishing object, determines a result based on a history of events from the one or more publishing object, and delivers the result to a read-only derived object of the at least one read-only derived object, the transactional object store system comprising:

a bus;

a memory connected to the bus, wherein the memory comprises computer executable instructions;

a communication unit connected to the bus;

a processor unit connected to the bus, wherein the processor unit executes the computer executable instructions to direct the transactional object store system to;

execute a transaction received from a client of the at least one client, wherein the transaction comprises one of reading a read-only derived object of the at least one read-only derived object, reading another object or writing another object, and wherein the transaction ends with one of a decision to request committing the transaction or a decision to request aborting the transaction;

responsive to a decision to request committing the transaction, wherein the transaction comprises writing one of the at least one publishing object, deliver events to event stream processing queries, and for executing the delivered event stream processing queries in parallel with the executing of the transaction; and

responsive to a decision to request committing a transaction that comprises reading one of the at least one read-only derived object, perform a validation to determine whether the transaction can proceed to be committed, whether the transaction should abort, or whether the validation should delay waiting for one or more event stream processing queries to complete,

wherein if a first transaction updates a publishing object that triggers an event processing query that updates a derived object, any second transaction occurring logically later must see the updated value of the derived object.

15. The transactional object store system of claim 14, wherein the processor unit further executes the computer executable instructions to direct the transactional object store system to:

assign a tentative logical time to the transaction;

remember latest read and write times for objects recently read and written; and

use the tentative logical time to determine whether it is necessary to perform one of;

adjusting the tentative logical time;

entering an optimistic state wherein the transaction is valid only if the validation succeeds; and

aborting the transaction.

16. The transactional object store system of claim 15, wherein the validation succeeds if a particular derived object does not change in a particular range of logical times.

17. The transactional object store system of claim 16, wherein the transaction is aborted if the particular derived object changes in the particular range of logical times.

18. The transactional object store system of claim 14, wherein the transaction comprises a reading operation, and wherein the tentative logical time is adjusted according to whether a latest operation on the object was a read operation or a write operation.

19. The transactional object store system of claim 14, wherein the transaction comprises a writing operation, and wherein the tentative logical time is adjusted according to a time of a latest read or write operation.

20. The transactional object store system of claim 14, wherein the transactional object store system comprises an ObjectGrid transactional system.