Processing element management in a streaming data system

• US 9,535,707 B2
• Filed: 12/10/2012
• Issued: 01/03/2017
• Est. Priority Date: 01/30/2012
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Branson, Michael J., Cradick, Ryan K., Santosuosso, John M., Schulz, Brandon W.
• Primary Examiner(s): Keehn, Richard G
• Assistant Examiner(s): Ahmed, Mohammed
• Application Number:
  US13/709,405
• Publication Number:
  US 20130198489A1
• Time in Patent Office: 1,485 Days
• Field of Search: 709/217, 709/223, 709/226, 709/231, 709/232
• US Class Current: 1/1
• CPC Class Codes: G06F 2209/502 Proximity
• CPC Class Codes: G06F 9/44 Arrangements for executing specific programs
• CPC Class Codes: G06F 9/4881 Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues
• CPC Class Codes: G06F 9/5011 the resources being hardware resources other than CPUs, Servers and Terminals
• CPC Class Codes: G06F 9/505 considering the load

Abstract

Stream applications may inefficiently use the hardware resources that execute the processing elements of the data stream. For example, a compute node may host four processing elements and execute each using a CPU. However, other CPUs on the compute node may sit idle. To take advantage of these available hardware resources, a stream programmer may identify one or more processing elements that may be cloned. The cloned processing elements may be used to generate a different execution path that is parallel to the execution path that includes the original processing elements. Because the cloned processing elements contain the same operators as the original processing elements, the data stream that was previously flowing through only the original processing element may be split and sent through both the original and cloned processing elements. In this manner, the parallel execution path may use underutilized hardware resources to increase the throughput of the data stream.

Claims

1. A method, comprising:

receiving streaming data to be processed by a plurality of processing elements, each comprising one or more operators, the operators processing at least a portion of the received data by operation of one or more computer processors;

establishing an operator graph of the operators, the operator graph defining at least one execution path in which a first operator of the operators is configured to receive data tuples from at least one upstream operator and transmit data tuples to at least one downstream operator;

identifying, relative to predefined criteria, a first and second underutilized hardware resource in a computing system that executes the operators;

cloning a first processing element of the plurality of processing elements such that the cloned processing element comprises the same one or more operators as the first processing element;

determining respective communication speeds between a hardware resource hosting the first operator and each of the first and second underutilized hardware resources, wherein the first operator is one of upstream and downstream of the cloned processing element in the operator graph;

selecting, based on the respective communication speeds, one of the first and second underutilized hardware resources to host the cloned processing element;

generating, after determining to clone the first processing element, a first execution path comprising the cloned processing element, the first execution path is configured to process at least a portion of the received streaming data using the selected underutilized hardware resource, wherein the first execution path executes in parallel to a previously configured second execution path that includes the first processing element; and

activating, in the operator graph downstream from the first and second execution paths, a second processing element comprising a merge operator that merges data tuples received from both the first and second execution paths into a single data stream.

2. The method of claim 1, further comprising:

activating in the operator graph upstream from the cloned and first processing elements a third processing element comprising a split operator that transmits data tuples to both the first and second execution paths.

3. The method of claim 2, further comprising, inserting the cloned, second, and third processing elements into the operator graph while the plurality of processing elements are processing the received streaming data.

4. The method of claim 1, wherein the underutilized hardware resource is at least one of:

a CPU and a portion of memory.

5. The method of claim 4, wherein the underutilized hardware resource is a CPU that is not currently executing one of the operators of one of the plurality of processing elements.

6. The method of claim 1, further comprising:

cloning a second processing element of the plurality of processing elements to generate a second cloned processing element comprising the same one or more operators as the second processing element, wherein the second processing element is directly connected to the first processing element in the second execution path; and

processing the received streaming data in the first execution path that comprises the second cloned processing element, wherein the second cloned processing element processes the received streaming data using the underutilized hardware resource.

7. The method of claim 1, further comprising determining whether the first processing element is cloneable, wherein a cloneable processing element is able to process the received data tuples in a different order than an order that the data tuples were received.

8. A method, comprising:

receiving streaming data to be processed by a plurality of processing elements, each comprising one or more operators, the operators processing at least a portion of the received data by operation of one or more computer processors;

establishing an operator graph of the operators, the operator graph defining at least one execution path in which a first operator of the operators is configured to receive data tuples from at least one upstream operator and transmit data tuples to at least one downstream operator;

identifying, relative to predefined criteria, a first and second underutilized hardware resource in a computing system that executes the operators;

cloning a first processing element of the plurality of processing elements such that the cloned processing element comprises the same one or more operators as the first processing element;

determining respective communication speeds between a hardware resource hosting the first operator and each of the first and second underutilized hardware resources, wherein the first operator is one of upstream and downstream of the cloned processing element in the operator graph;

selecting, based on the respective communication speeds, one of the first and second underutilized hardware resources to host the cloned processing element;

generating, after determining to clone the first processing element, a first execution path comprising the cloned processing element, the first execution path is configured to process at least a portion of the received streaming data using the selected underutilized hardware resource, wherein the first execution path executes in parallel to a previously configured second execution path that includes the first processing element; and

activating, in the operator graph downstream from the first and second execution paths, a second processing element comprising a merge operator that merges data tuples received from both the first and second execution paths into a single data stream, wherein the merge operator is activated after data tuples have already been received and processed by the second processing element.