Internode Data Communications In A Parallel Computer

• US 20130117764A1
• Filed: 11/07/2011
• Published: 05/09/2013
• Est. Priority Date: 11/07/2011
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Archer, Charles J., Blocksome, Michael A., Miller, Douglas R., Parker, Jeffrey J., Ratterman, Joseph D., Smith, Brian E.
• Granted Patent: US 8,528,004 B2
• Time in Patent Office: Days
• US Class Current: 719/314
• CPC Class Codes: G06F 9/544 Buffers; Shared memory; Pipes

Abstract

Internode data communications in a parallel computer that includes compute nodes that each include main memory and a messaging unit, the messaging unit including computer memory and coupling compute nodes for data communications, in which, for each compute node at compute node boot time: a messaging unit allocates, in the messaging unit'"'"'s computer memory, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node; receives, prior to initialization of a particular process on the compute node, a data communications message intended for the particular process; and stores the data communications message in the message buffer associated with the particular process. Upon initialization of the particular process, the process establishes a messaging buffer in main memory of the compute node and copies the data communications message from the message buffer of the messaging unit into the message buffer of main memory.

Claims

1-7. -7. (canceled)

8. An apparatus for internode data communications in a parallel computer, the parallel computer comprising a plurality of compute nodes, each compute node comprising main computer memory and a messaging unit, the messaging unit comprising computer memory, the messaging unit comprising a module of automated computing machinery coupling compute nodes for data communications, the apparatus comprising a computer processor, a computer memory operatively coupled to the computer processor, the computer memory having disposed within it computer program instructions that, when executed, cause the apparatus to carry out the steps of:

for each compute node at compute node boot time;

allocating, by the messaging unit in the messaging unit'"'"'s computer memory, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node;

receiving, by the messaging unit prior to initialization of a particular process on the compute node, a data communications message intended for the particular process;

storing the data communications message in the message buffer associated with the particular process;

upon initialization of the particular process, establishing, by the particular process, a messaging buffer in main memory of the compute node; and

copying, by the particular process, the data communications message from the message buffer of the messaging unit into the message buffer of main memory.

9. The apparatus of claim 8 further comprising computer program instructions that, when executed, cause the apparatus to carry out the steps of:

maintaining, by each messaging unit, a status of unused message buffers in the messaging unit'"'"'s memory; and

requesting, by a process on a compute node via a broadcast operation, availability of messaging unit message buffers;

receiving, from each messaging unit, an indication of available messaging unit message buffers; and

sending, by the process, a data communications message to an available messaging unit message buffer with an instruction to initialize an on-demand process associated with that messaging unit message buffer.

10. The apparatus of claim 8 further comprising computer program instructions that, when executed, cause the apparatus to carry out the steps of:

receiving, by a messaging unit, a request to initialize an on-demand process to execute a task, including receiving a data communications message intended for the on-demand process;

storing, by the messaging unit in the messaging unit'"'"'s computer memory, the data communications message intended for the on-demand process in an available message buffer;

initializing the on-demand process;

establishing, by the on-demand process upon initialization, a messaging buffer in main memory of the compute node;

copying, by the on-demand process, the data communications message from the message buffer of the messaging unit into the message buffer of main memory; and

upon completion of the task, releasing, by the on-demand process, the message buffer in the main memory and the message buffer in the messaging unit.

11. The apparatus of claim 8 wherein:

the parallel computer comprises a parallel active messaging interface (‘

PAMI’

) and the plurality of compute nodes execute a parallel application, the PAMI comprises 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 endpoints coupled for data communications through the PAMI; and

each process comprises an endpoint.

12. The apparatus of claim 11 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.

13. The apparatus of claim 11 wherein each context carries out, through post and advance functions, data communications for the parallel application on data communications resources in the exclusive possession of that context.

14. The apparatus of claim 11 wherein each context carries out data communications operations independently and in parallel with other contexts.

15. A computer program product for internode data communications in a parallel computer, the parallel computer comprising a plurality of compute nodes, each compute node comprising main computer memory and a messaging unit, the messaging unit comprising computer memory, the messaging unit comprising a module of automated computing machinery coupling compute nodes for data communications, the computer program product disposed upon a computer readable storage medium, the computer program product comprising computer program instructions that, when executed, cause a computer to carry out the steps of:

for each compute node at compute node boot time;

allocating, by the messaging unit in the messaging unit'"'"'s computer memory, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node;

receiving, by the messaging unit prior to initialization of a particular process on the compute node, a data communications message intended for the particular process;

storing the data communications message in the message buffer associated with the particular process;

upon initialization of the particular process, establishing, by the particular process, a messaging buffer in main memory of the compute node; and

copying, by the particular process, the data communications message from the message buffer of the messaging unit into the message buffer of main memory.

16. The computer program product of claim 15 further comprising computer program instructions that, when executed, cause the computer to carry out the steps of:

maintaining, by each messaging unit, a status of unused message buffers in the messaging unit'"'"'s memory; and

requesting, by a process on a compute node via a broadcast operation, availability of messaging unit message buffers;

receiving, from each messaging unit, an indication of available messaging unit message buffers; and

sending, by the process, a data communications message to an available messaging unit message buffer with an instruction to initialize an on-demand process associated with that messaging unit message buffer.

17. The computer program product of claim 15 further comprising computer program instructions that, when executed, cause the computer to carry out the steps of:

receiving, by a messaging unit, a request to initialize an on-demand process to execute a task, including receiving a data communications message intended for the on-demand process;

storing, by the messaging unit in the messaging unit'"'"'s computer memory, the data communications message intended for the on-demand process in an available message buffer;

initializing the on-demand process;

establishing, by the on-demand process upon initialization, a messaging buffer in main memory of the compute node;

copying, by the on-demand process, the data communications message from the message buffer of the messaging unit into the message buffer of main memory; and

upon completion of the task, releasing, by the on-demand process, the message buffer in the main memory and the message buffer in the messaging unit.

18. The computer program product of claim 15 wherein:

the parallel computer comprises a parallel active messaging interface (‘

PAMI’

) and the plurality of compute nodes execute a parallel application, the PAMI comprises 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 endpoints coupled for data communications through the PAMI; and

each process comprises an endpoint.

19. The computer program product of claim 18 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.

20. The computer program product of claim 18 wherein each context carries out, through post and advance functions, data communications for the parallel application on data communications resources in the exclusive possession of that context.

21. The computer program product of claim 18 wherein each context carries out data communications operations independently and in parallel with other contexts.

22-23. -23. (canceled)