Data communications in a parallel active messaging interface of a parallel computer

• US 8,789,067 B2
• Filed: 10/24/2012
• Issued: 07/22/2014
• Est. Priority Date: 12/03/2010
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Davis, Kristan D., Faraj, Daniel A.
• Primary Examiner(s): DAO, TUAN C.
• Application Number:
  US13/659,370
• Publication Number:
  US 20130061244A1
• Time in Patent Office: 636 Days
• Field of Search: None
• US Class Current: 719/313
• CPC Class Codes: G06F 15/17318 Parallel communications techniques, e.g. gather, scatter, reduce, roadcast, multicast, all to all

Abstract

Algorithm selection for data communications in a parallel active messaging interface (‘PAMI’) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI, including associating in the PAMI data communications algorithms and ranges of message sizes so that each algorithm is associated with a separate range of message sizes; receiving in an origin endpoint of the PAMI a data communications instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint, the data communications message characterized by a message size; selecting, from among the associated algorithms and ranges, a data communications algorithm in dependence upon the message size; and transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.

Claims

1. A method of algorithm selection for data communications in a parallel active messaging interface (‘

PAMI’

) of a parallel computer, the parallel computer comprising a plurality of compute nodes that execute a parallel application, the PAMI comprising data communications endpoints, each endpoint comprising a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task, the compute nodes and the endpoints coupled for data communications through the PAMI and through data communications resources, the method comprising;

associating in the PAMI data communications algorithms and ranges of message sizes so that each algorithm is associated with a separate range of message sizes;

receiving in an origin endpoint of the PAMI a data communications instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint, the data communications message characterized by a message size;

selecting, from among the associated algorithms and ranges, a data communications algorithm in dependence upon the message size, a number of ranges, an upper boundary value and an index identifying a range containing the message size;

transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.

2. The method of claim 1 wherein the ranges vary in magnitude.

3. The method of claim 1 wherein each range is characterized by an upper boundary value, and selecting a data communications algorithm further comprises selecting a data communications algorithm according to:

4. The method of claim 1 wherein:

each client comprises a collection of data communications resources dedicated to the exclusive use of an application-level data processing entity;

each context comprises a subset of the collection of data processing resources of a client, context functions, and a work queue of data transfer instructions to be performed by use of the subset through the context functions operated by an assigned thread of execution; and

each task represents a process of execution of the parallel application.

5. The method of claim 1 wherein each context carries out, through post and advance functions, data communications for the parallel application on data communications resources in exclusive possession of that context.

6. The method of claim 1 wherein each context carries out data communications operations independently and in parallel with other contexts.