Controlling Access To A Resource In A Distributed Computing System With A Distributed Access Request Queue

Abstract

Controlling access to a resource in a distributed computing system that includes nodes having a status field, a next field, a source data buffer, and that are characterized by a unique node identifier, where controlling access includes receiving a request for access to the resource implemented as an active message that includes the requesting node's unique node identifier, the value stored in the requesting node's source data buffer, and an instruction to perform a reduction operation with the value stored in the requesting node's source data buffer and the value stored in the receiving node's source data buffer; returning the requesting node's unique node identifier as a result of the reduction operation; and updating the status and next fields to identify the requesting node as a next node to have sole access to the resource.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The field of the invention is data processing, or, more specifically, methods, apparatus, and products for controlling access to a resource in a distributed computing system.[0003]2. Description of Related Art[0004]The development of the EDVAC computer system of 1948 is often cited as the beginning of the computer era. Since that time, computer systems have evolved into extremely complicated devices. Today's computers are much more sophisticated than early systems such as the EDVAC. Computer systems typically include a combination of hardware and software components, application programs, operating systems, processors, buses, memory, input / output devices, and so on. As advances in semiconductor processing and computer architecture push the performance of the computer higher and higher, more sophisticated computer software has evolved to take advantage of the higher performance of the hardware, resulting in computer syst...

AI Technical Summary

Benefits of technology

[0016]For each of the other receiving nodes, controlling access to the resource includes returning, to the requesting node, as a result of the reduction operation, a value other than the requesting node's unique node identifier. Returning a value other than the requesting node's unique node identifier includes storing a predefined value in the source data buffer a...

Problems solved by technology

Since that time, computer systems have evolved into extremely complicated devices.

It is far more difficult to construct a computer with a single fast processor than one with many slow processors with the same throughput.

There are also certain theoretical limits to the potential speed of serial processors.

After that point adding more processors does not yield any more throughput but only increases the overhead and cost.

Shared memory processing needs additional locking for the data and imposes the overhead of additional processor and bus cycles and also serializes some portion of the algorithm.

Message passing processing uses high-speed data communications networks and message buffers, but this communication adds transfer overhead on the data communications networks as well as additional memory need for message buffers and latency in the data communications among nodes.

Although a tree network typically is inefficient in point to point communication, a tree network does provide high bandwidth and low latency for certain collective operations, message passing operations where all compute nodes participate simultaneously, such as, for example, an allgather operation.

Although distributed computing environments are more computationally powerful and efficient in data processing than many non-distributed computing environments, such distributed computing environments still present substantial challenges to the science of automated computing machinery.

Resource allocation and access among nodes in such distributed computing environments, for example, is just one area of distributed computing that present substantial challenges to the science of automated computing machinery.

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