Title
Evaluating Quality Of Service Traffic Classes On The Megafly Network
Abstract
An emerging trend in High Performance Computing (HPC) systems that use hierarchical topologies (such as dragonfly) is that the applications are increasingly exhibiting high run-to-run performance variability. This poses a significant challenge for application developers, job schedulers, and system maintainers. One approach to address the performance variability is to use newly proposed network topologies such as megafly (or dragonfly+) that offer increased path diversity compared to a traditional fully connected dragonfly. Yet another approach is to use quality of service (QoS) traffic classes that ensure bandwidth guarantees. In this work, we select HPC application workloads that have exhibited performance variability on current 2-D dragonfly systems. We evaluate the baseline performance expectations of these workloads on megafly and 1-D dragonfly network models with comparably similar network configurations. Our results show that the megafly network, despite using fewer virtual channels (VCs) for deadlock avoidance than a dragonfly, performs as well as a fully connected 1-D dragonfly network. We then exploit the fact that megafly networks require fewer VCs to incorporate QoS traffic classes. We use bandwidth capping and traffic differentiation techniques to introduce multiple traffic classes in megafly networks. In some cases, our results show that QoS can completely mitigate application performance variability while causing minimal slowdown to the background network traffic.
Year
DOI
Venue
2019
10.1007/978-3-030-20656-7_1
HIGH PERFORMANCE COMPUTING, ISC HIGH PERFORMANCE 2019
Field
DocType
Volume
Computer science,Transport engineering,Quality of service
Conference
11501
ISSN
Citations 
PageRank 
0302-9743
2
0.40
References 
Authors
0
10
Name
Order
Citations
PageRank
Mubarak Misbah113414.22
neil mcglohon261.51
Malek Musleh321.07
Eric Borch481.55
Rob Ross5184.81
Ram Huggahalli635820.94
Sudheer Chunduri7213.26
Scott Parker820.40
C. Carothers9253.78
Kalyan Kumaran1020.40