@inproceedings {Simula.simula.1134,
	title = {Topology Agnostic Dynamic Quick Reconfiguration for Large-Scale Interconnection Networks},
	journal = {Proceedings of The 12th IEEE/ACM International Symposium on Cluster, Cloud and Grid Computing},
	year = {2012},
	month = {May},
	publisher = {IEEE},
	type = {Conference},
	abstract = {Toleration of faults in the interconnection networks is of vital importance in todays huge computer installations. Still, the existing solutions are short of being satisfactory. They require that the system defaults into a routing algorithm that is inferior to the original, either in terms of performance, or in terms of the need for virtual channels, or both. Furthermore, since support for dynamic reconfiguration is not supported in current hardware, existing methods require the system to be halted while reconfiguration takes place in order to avoid deadlocks. In this paper we present a method that efficiently generates a new routing function in the presence of faults. The new routing function only reroutes the traffic that is affected by the fault, so that the performance of the original routing function is preserved to the extent possible. No specific functionality in the switches is required, we only require exactly the same number of virtual channels in the presence of faults as the original routing algorithm did. Finally, the new routing function is compatible with the old one, so that deadlock free dynamic transition between the old and the new routing function is immediately available. This means that our solution can easily be implemented on current InfiniBand platforms, e.g. through the OFED software stack. We demonstrate that the method is workable for meshes, tori and fat-trees, and that it is able to guarantee one-fault tolerance for all of these topologies.},
	author = {Frank Olaf {Sem-Jacobsen} and Lysne, Olav},
	editor = {Balaji, Pavan and Buyya, Rajkumar}
}
@inproceedings {Simula.simula.364,
	title = {On the Relation Between Congestion Control, Switch Arbitration and Fairness},
	journal = {11th IEEE/ACM International Symposium on Cluster, Cloud, and Grid Computing (CCGrid 2011)},
	year = {2011},
	month = {May},
	pages = {342-351},
	publisher = {IEEE},
	type = {Conference},
	abstract = {In lossless interconnection networks such as InfiniBand, congestion control (CC) can be an effective mechanism to achieve high performance and good utilization of network resources. The InfiniBand standard describes CC functionality for detecting and resolving congestion, but the design decisions on how to implement this functionallity is left to the hardware designer. One must be cautious when making these design decisions not to introduce fairness problems, as our study shows. In this paper we study the relationship between congestion control, switch arbitration, and fairness. Specifically, we look at fairness among different traffic flows arriving at a hot spot switch on different input ports, as CC is turned on. In addition we study the fairness among traffic flows at a switch where some flows are exclusive users of their input ports while other flows are sharing an input port (the parking lot problem). Our results show that the implementation of congestion control in a switch is vulnerable to unfairness if care is not taken. In detail, we found that a threshold hysteresis of more than one MTU is needed to resolve arbitration unfairness. Furthermore, to fully solve the parking lot problem, proper configuration of the CC parameters are required.},
	isbn = {978-1-4577-0129-0},
	doi = {10.1109/CCGrid.2011.67},
	author = {Ernst Gunnar {Gran} and Zahavi, Eitan and Reinemo, Sven-Arne and Skeie, Tor and Shainer, Gilad and Lysne, Olav},
	editor = {Buyya, Rajkumar}
}
@inproceedings {Simula.simula.358,
	title = {A Scalable Method for Signalling Dynamic Reconfiguration Events With OpenSM},
	journal = {11th IEEE/ACM International Symposium on Cluster, Cloud, and Grid Computing (CCGrid 2011)},
	year = {2011},
	pages = {332-341},
	publisher = {IEEE Computer Society Press},
	type = {Conference},
	abstract = {Rerouting around faulty components, on-the-fly policy changes, and migration of jobs all require reconfiguration of data structures in the Queue Pairs residing in the hosts on an InfiniBand cluster. In addition to a proper implementation at the host, the subnet manager needs to implement a scalable method for signaling reconfiguration events to the hosts. In this paper we propose and evaluate three different implementations for signalling dynamic reconfiguration events with OpenSM. Through our evaluation we demonstrate a scalable solution for signalling host-side reconfiguration events in an InfiniBand network based on an example where dynamic network reconfiguration combined with a topology-agnostic routing function is used to avoid malfunctioning components. Through measurements on our test-cluster and an analytical study we show that our best proposal reduces reconfiguration latency by more than 90\% and in certain situations eliminates it completely. Furthermore, the processing overhead in the subnet manager is shown to be minimal.},
	isbn = {978-1-4577-0129-0},
	author = {Wei Lin {Guay} and Reinemo, Sven-Arne},
	editor = {Buyya, Rajkumar}
}
@inproceedings {Sem-jacobsen.2006.2,
	title = {Combining Source Routing and Dynamic Fault Tolerance},
	journal = {Proceedings of The 18{\textquoteright}th International Symposium on Computer Architecture and High Performance Computing (SBAC-PAD)},
	year = {2006},
	month = {October},
	pages = {151-158},
	publisher = {IEEE Computer Society},
	type = {Conference},
	address = {Washington, DC, USA},
	abstract = {An increasing amount of current and emerging interconnect technologies rely on source routing to forward packets through the network. It is therefore important to develop methods for fault tolerance that are well suited for source routed networks. Dynamic fault tolerance allows the network to remain available through the occurrence of faults, as opposed to static fault tolerance which requires the network to be halted to reconfigure it. Source routing readily supports the source node choosing a different path when a fault occurs, but using this approach, packets already in the network will be lost. Local dynamic fault tolerance, where the packet is routed around the fault locally, would prevent much of the traffic being lost during failures, but this is cumbersome to achieve in source routed networks since packets encountering a fault will need to follow a path different from that encoded in the packet header. In this paper we present a mechanism to achieve local dynamic fault tolerance in source routed fat trees, a topology that has widespread use in supercomputer systems, and compare it with endpoint dynamic fault tolerance. We also show that by combining the two approaches we achieve performance superior to any of the two individually.},
	isbn = {0-7695-2704-3},
	author = {Frank Olaf {Sem-Jacobsen} and Lysne, Olav and Skeie, Tor},
	editor = {Alberto F. {De Souza} and Buyya, Rajkumar and Wagner {Meira, Jr.}}
}
