EXECUTING CONTINUOUS EVENT PROCESSING (CEP) QUERIES IN PARALLEL

• US 20140236983A1
• Filed: 02/19/2013
• Published: 08/21/2014
• Est. Priority Date: 02/19/2013
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Srinivasan, Anand, Alves, Alexandre de Castro
• Granted Patent: US 9,390,135 B2
• Time in Patent Office: Days
• US Class Current: 707/769
• CPC Class Codes: G06F 16/24532 of parallel queries
• CPC Class Codes: G06F 16/24565 Triggers; Constraints
• CPC Class Codes: G06F 16/24568 Data stream processing; Continuous queries
• CPC Class Codes: G06F 16/2474 Sequence data queries, e.g. querying versioned data

Abstract

A continuous event processing (CEP) query processor determines how and when a CEP query can be processed in a concurrent manner, such that multiple threads of execution can concurrently perform at least some of the CEP query'"'"'s operations concurrently with each other. According to one technique, a user can instruct a CEP query processor to attempt to execute a CEP query in a concurrent manner. The CEP query processor responsively determines whether the CEP query'"'"'s execution, or parts thereof, can be made concurrent based on certain constraints that can depend on inheritance and operation type. Based on this determination, the CEP query processor can execute at least certain parts of a CEP query in parallel relative to the same event within an event stream.

Claims

1. A computer-readable memory storing a plurality of instructions for causing a processor to perform operations, the plurality of instructions comprising:

instructions that cause the processor to split a continuous event processing (CEP) query into a plurality of separate operators;

instructions that cause the processor to determine a separate constraint for each particular operator within the plurality of separate operators;

instructions that cause the processor to determine a constraint for the CEP query based at least in part on the constraints that the processor determined for the plurality of separate operators; and

instructions that cause the processor to determine, based on the constraint for the CEP query, whether at least a part of the CEP query can be executed in a concurrent manner; and

instructions that cause the processor to spawn multiple threads of execution that concurrently process events from an event stream in response to determining that at least part of the CEP query can be executed in a concurrent manner.

2. The computer-readable memory of claim 1, wherein the plurality of instructions comprises instructions that cause the processor to determine a constraint for the CEP query based at least in part on a constraint that is associated with the event stream.

3. The computer-readable memory of claim 1, wherein the instructions that cause the processor to determine the separate constraint for each particular operator within the plurality of separate operators comprise instructions that cause the processor to determine a constraint for the particular operator based at least in part on one or more constraints of one or more other operators from which the particular operator receives input.

4. The computer-readable memory of claim 1, wherein the instructions that cause the processor to determine the separate constraint for each particular operator within the plurality of separate operators comprise instructions that cause the processor to determine a constraint for the particular operator based at least in part on whether an operation type of the particular operator is a filtering operation type.

5. The computer-readable memory of claim 1, wherein the instructions that cause the processor to determine the separate constraint for each particular operator within the plurality of separate operators comprise instructions that cause the processor to determine a constraint for the particular operator by determining a most constrained constraint within a set of constraints including (a) constraints of all other operators from which the particular operator receives input and (b) a constraint associated with an operation type of the particular operator.

6. The computer-readable memory of claim 1, wherein the plurality of instructions further comprise:

instructions that cause the processor to merge, into a single shared operator, (a) a first operator that is used by a first CEP query that processes events in the event stream, and (b) a second operator that is used by a second CEP query that also processes events in the event stream, in response to determining that the first operator and the second operator both perform a particular type of operation.

7. The computer-readable memory of claim 1, wherein the plurality of instructions further comprise:

instructions that cause the processor to merge, into a single shared operator, (a) a first operator that is used by a first CEP query that processes events in the event stream, and (b) a second operator that is used by a second CEP query that also processes events in the event stream, in response to determining that the first operator and the second operator both perform a particular type of operation;

wherein the instructions that cause the processor to determine the separate constraint for each particular operator within the plurality of separate operators comprise instructions that cause the processor to determine a constraint for a third operator, which receives input from the shared operator, based at least in part on a constraint of the shared operator;

wherein the instructions that cause the processor to determine the separate constraint for each particular operator within the plurality of separate operators comprise instructions that cause the processor to determine a constraint for a fourth operator, which receives input from the shared operator, based at least in part on the constraint of the shared operator;

wherein the third operator is used by the first CEP query and is not used by the second CEP query;

wherein the fourth operator is used by the second CEP query and is not used by the first CEP query.

8. A system for processing a data stream of events, the system comprising:

a memory storing a plurality of instructions; and

a processor coupled to the memory, the processor configured to execute the plurality of instructions to;

split a continuous event processing (CEP) query into a plurality of separate operators;

determine a separate constraint for each particular operator within the plurality of separate operators;

determine a constraint for the CEP query based at least in part on the constraints that the processor determined for the plurality of separate operators; and

determine, based on the constraint for the CEP query, whether at least a part of the CEP query can be executed in a concurrent manner; and

spawn multiple threads of execution that concurrently process events from an event stream in response to determining that at least part of the CEP query can be executed in a concurrent manner.

9. The system of claim 8, wherein the processor is configured to determine a constraint for the CEP query based at least in part on a constraint that is associated with the event stream.

10. The system of claim 8, wherein the processor is configured to determine the separate constraint for each particular operator within the plurality of separate operators at least in part by determining a constraint for the particular operator based at least in part on one or more constraints of one or more other operators from which the particular operator receives input.

11. The system of claim 8, wherein the processor is configured to determine the separate constraint for each particular operator within the plurality of separate operators at least in part by determining a constraint for the particular operator based at least in part on whether an operation type of the particular operator is a filtering operation type.

12. The system of claim 8, wherein the processor is configured to determine the separate constraint for each particular operator within the plurality of separate operators at least in part by determining a constraint for the particular operator by determining a most constrained constraint within a set of constraints including (a) constraints of all other operators from which the particular operator receives input and (b) a constraint associated with an operation type of the particular operator.

13. The system of claim 8, wherein the processor is configured to merge, into a single shared operator, (a) a first operator that is used by a first CEP query that processes events in the event stream, and (b) a second operator that is used by a second CEP query that also processes events in the event stream, in response to determining that the first operator and the second operator both perform a particular type of operation.

14. The system of claim 8, wherein the processor is configured to merge, into a single shared operator, (a) a first operator that is used by a first CEP query that processes events in the event stream, and (b) a second operator that is used by a second CEP query that also processes events in the event stream, in response to determining that the first operator and the second operator both perform a particular type of operation;

wherein the processor is configured to determine a constraint for a third operator, which receives input from the shared operator, based at least in part on a constraint of the shared operator;

wherein the processor is configured to determine a constraint for a fourth operator, which receives input from the shared operator, based at least in part on the constraint of the shared operator;

wherein the third operator is used by the first CEP query and is not used by the second CEP query;

wherein the fourth operator is used by the second CEP query and is not used by the first CEP query.

15. A method for processing a data stream of events, the method comprising:

splitting a continuous event processing (CEP) query into a plurality of separate operators;

determining a separate constraint for each particular operator within the plurality of separate operators;

determining a constraint for the CEP query based at least in part on the constraints that the processor determined for the plurality of separate operators; and

determining, based on the constraint for the CEP query, whether at least a part of the CEP query can be executed in a concurrent manner; and

spawning multiple threads of execution that concurrently process events from an event stream in response to determining that at least part of the CEP query can be executed in a concurrent manner.

16. The method of claim 15, further comprising:

determining a constraint for the CEP query based at least in part on a constraint that is associated with the event stream.

17. The method of claim 15, wherein determining the separate constraint for each particular operator within the plurality of separate operators comprises determining a constraint for the particular operator based at least in part on one or more constraints of one or more other operators from which the particular operator receives input.

18. The method of claim 15, wherein determining the separate constraint for each particular operator within the plurality of separate operators comprises determining a constraint for the particular operator based at least in part on whether an operation type of the particular operator is a filtering operation type.

19. The method of claim 15, further comprising:

merging, into a single shared operator, (a) a first operator that is used by a first CEP query that processes events in the event stream, and (b) a second operator that is used by a second CEP query that also processes events in the event stream, in response to determining that the first operator and the second operator both perform a particular type of operation.

20. The method of claim 15, further comprising:

merging, into a single shared operator, (a) a first operator that is used by a first CEP query that processes events in the event stream, and (b) a second operator that is used by a second CEP query that also processes events in the event stream, in response to determining that the first operator and the second operator both perform a particular type of operation;

wherein determining the separate constraint for each particular operator within the plurality of separate operators comprises determining a constraint for a third operator, which receives input from the shared operator, based at least in part on a constraint of the shared operator;

wherein determining the separate constraint for each particular operator within the plurality of separate operators comprises determining a constraint for a fourth operator, which receives input from the shared operator, based at least in part on the constraint of the shared operator;

wherein the third operator is used by the first CEP query and is not used by the second CEP query;

wherein the fourth operator is used by the second CEP query and is not used by the first CEP query.