Performance benefits of virtual channels and adaptive routing: an application-driven study

Research output: Chapter in Book/Report/Conference proceedingConference contribution

9 Citations (Scopus)

Abstract

Recent research on multiprocessor interconnection networks has primarily focussed on wormhole switching, virtual channel flow control and routing algorithms. These architectural features are aimed at enhancing the network performance by reducing the network latency, which in turn should improve the overall system performance. Many research results support this design philosophy by claiming significant reduction in average message latency. However, these conclusions are drawn using synthetic workloads that may not necessarily capture the behavior of real applications. In this paper, we have used parallel applications for a closer examination of the network behavior. In particular, the performance benefit from enhancing a 2-D mesh with virtual channels (VCs) and a routing algorithm (oblivious or fully adaptive) is examined with five shared memory applications using an execution-driven simulator, SPASM. In order to analyze the performance implications in greater detail, we also consider other parameters that have a direct bearing on network traffic. These are the number of processors used to solve a problem, problem size and memory consistency model. Simulation results show that VCs can reduce the network latency to varying degrees depending on the application. Similar gain is possible with a fully adaptive routing algorithm compared to the oblivious routing. However, with respect to the overall execution time, the performance benefit using these enhancements is negligible. Moreover, this benefit is negated when we consider the cost of implementing the VCs. These results suggest that the performance rewards may not justify the cost of these enhancements. Rather, we need to emphasize on improving the raw network bandwidth by simpler and improved router designs.

Original languageEnglish (US)
Title of host publicationProceedings of the International Conference on Supercomputing
PublisherACM
Pages140-147
Number of pages8
StatePublished - 1997
EventProceedings of the 1997 International Conference on Supercomputing - Vienna, Austria
Duration: Jul 7 1997Jul 11 1997

Other

OtherProceedings of the 1997 International Conference on Supercomputing
CityVienna, Austria
Period7/7/977/11/97

Fingerprint

Routing algorithms
Data storage equipment
Interconnection networks (circuit switching)
Channel flow
Network performance
Adaptive algorithms
Routers
Flow control
Costs
Simulators
Bandwidth

All Science Journal Classification (ASJC) codes

  • Computer Science(all)

Cite this

Vaidya, A. S., Sivasubramaniam, A., & Das, C. (1997). Performance benefits of virtual channels and adaptive routing: an application-driven study. In Proceedings of the International Conference on Supercomputing (pp. 140-147). ACM.
Vaidya, Aniruddha S. ; Sivasubramaniam, Anand ; Das, Chitaranjan. / Performance benefits of virtual channels and adaptive routing : an application-driven study. Proceedings of the International Conference on Supercomputing. ACM, 1997. pp. 140-147
@inproceedings{c586dd2b98b3471b8cf71ea97f7aaac5,
title = "Performance benefits of virtual channels and adaptive routing: an application-driven study",
abstract = "Recent research on multiprocessor interconnection networks has primarily focussed on wormhole switching, virtual channel flow control and routing algorithms. These architectural features are aimed at enhancing the network performance by reducing the network latency, which in turn should improve the overall system performance. Many research results support this design philosophy by claiming significant reduction in average message latency. However, these conclusions are drawn using synthetic workloads that may not necessarily capture the behavior of real applications. In this paper, we have used parallel applications for a closer examination of the network behavior. In particular, the performance benefit from enhancing a 2-D mesh with virtual channels (VCs) and a routing algorithm (oblivious or fully adaptive) is examined with five shared memory applications using an execution-driven simulator, SPASM. In order to analyze the performance implications in greater detail, we also consider other parameters that have a direct bearing on network traffic. These are the number of processors used to solve a problem, problem size and memory consistency model. Simulation results show that VCs can reduce the network latency to varying degrees depending on the application. Similar gain is possible with a fully adaptive routing algorithm compared to the oblivious routing. However, with respect to the overall execution time, the performance benefit using these enhancements is negligible. Moreover, this benefit is negated when we consider the cost of implementing the VCs. These results suggest that the performance rewards may not justify the cost of these enhancements. Rather, we need to emphasize on improving the raw network bandwidth by simpler and improved router designs.",
author = "Vaidya, {Aniruddha S.} and Anand Sivasubramaniam and Chitaranjan Das",
year = "1997",
language = "English (US)",
pages = "140--147",
booktitle = "Proceedings of the International Conference on Supercomputing",
publisher = "ACM",

}

Vaidya, AS, Sivasubramaniam, A & Das, C 1997, Performance benefits of virtual channels and adaptive routing: an application-driven study. in Proceedings of the International Conference on Supercomputing. ACM, pp. 140-147, Proceedings of the 1997 International Conference on Supercomputing, Vienna, Austria, 7/7/97.

Performance benefits of virtual channels and adaptive routing : an application-driven study. / Vaidya, Aniruddha S.; Sivasubramaniam, Anand; Das, Chitaranjan.

Proceedings of the International Conference on Supercomputing. ACM, 1997. p. 140-147.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

TY - GEN

T1 - Performance benefits of virtual channels and adaptive routing

T2 - an application-driven study

AU - Vaidya, Aniruddha S.

AU - Sivasubramaniam, Anand

AU - Das, Chitaranjan

PY - 1997

Y1 - 1997

N2 - Recent research on multiprocessor interconnection networks has primarily focussed on wormhole switching, virtual channel flow control and routing algorithms. These architectural features are aimed at enhancing the network performance by reducing the network latency, which in turn should improve the overall system performance. Many research results support this design philosophy by claiming significant reduction in average message latency. However, these conclusions are drawn using synthetic workloads that may not necessarily capture the behavior of real applications. In this paper, we have used parallel applications for a closer examination of the network behavior. In particular, the performance benefit from enhancing a 2-D mesh with virtual channels (VCs) and a routing algorithm (oblivious or fully adaptive) is examined with five shared memory applications using an execution-driven simulator, SPASM. In order to analyze the performance implications in greater detail, we also consider other parameters that have a direct bearing on network traffic. These are the number of processors used to solve a problem, problem size and memory consistency model. Simulation results show that VCs can reduce the network latency to varying degrees depending on the application. Similar gain is possible with a fully adaptive routing algorithm compared to the oblivious routing. However, with respect to the overall execution time, the performance benefit using these enhancements is negligible. Moreover, this benefit is negated when we consider the cost of implementing the VCs. These results suggest that the performance rewards may not justify the cost of these enhancements. Rather, we need to emphasize on improving the raw network bandwidth by simpler and improved router designs.

AB - Recent research on multiprocessor interconnection networks has primarily focussed on wormhole switching, virtual channel flow control and routing algorithms. These architectural features are aimed at enhancing the network performance by reducing the network latency, which in turn should improve the overall system performance. Many research results support this design philosophy by claiming significant reduction in average message latency. However, these conclusions are drawn using synthetic workloads that may not necessarily capture the behavior of real applications. In this paper, we have used parallel applications for a closer examination of the network behavior. In particular, the performance benefit from enhancing a 2-D mesh with virtual channels (VCs) and a routing algorithm (oblivious or fully adaptive) is examined with five shared memory applications using an execution-driven simulator, SPASM. In order to analyze the performance implications in greater detail, we also consider other parameters that have a direct bearing on network traffic. These are the number of processors used to solve a problem, problem size and memory consistency model. Simulation results show that VCs can reduce the network latency to varying degrees depending on the application. Similar gain is possible with a fully adaptive routing algorithm compared to the oblivious routing. However, with respect to the overall execution time, the performance benefit using these enhancements is negligible. Moreover, this benefit is negated when we consider the cost of implementing the VCs. These results suggest that the performance rewards may not justify the cost of these enhancements. Rather, we need to emphasize on improving the raw network bandwidth by simpler and improved router designs.

UR - http://www.scopus.com/inward/record.url?scp=0030654244&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030654244&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:0030654244

SP - 140

EP - 147

BT - Proceedings of the International Conference on Supercomputing

PB - ACM

ER -

Vaidya AS, Sivasubramaniam A, Das C. Performance benefits of virtual channels and adaptive routing: an application-driven study. In Proceedings of the International Conference on Supercomputing. ACM. 1997. p. 140-147