A flow control mechanism to avoid message deadlock in k-ary n-cube networks

Carrión, Carmen; Beivide, Ramón; Gregorio, J.A.; Vallejo, F.

doi:10.1109/hipc.1997.634510

Cited by 57 publications

(40 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At each hop, packets that cannot use any of the adaptive channels that provide a minimal path to their respective destinations use the escape channel provided by the deterministic routing function. 6 Also, a static fault model with checkpointing is assumed. Detection of faults, checkpointing, and distribution of routing info is performed as part of the static fault model and, thus, will not be further discussed in this paper.…”

Section: Methodsmentioning

confidence: 99%

A routing methodology for achieving fault tolerance in direct networks

Gomez

Nordbotten

Flich

et al. 2006

IEEE Trans. Comput.

View full text Add to dashboard Cite

Abstract-Massively parallel computing systems are being built with thousands of nodes. The interconnection network plays a key role for the performance of such systems. However, the high number of components significantly increases the probability of failure. Additionally, failures in the interconnection network may isolate a large fraction of the machine. It is therefore critical to provide an efficient fault-tolerant mechanism to keep the system running, even in the presence of faults. This paper presents a new fault-tolerant routing methodology that does not degrade performance in the absence of faults and tolerates a reasonably large number of faults without disabling any healthy node. In order to avoid faults, for some source-destination pairs, packets are first sent to an intermediate node and then from this node to the destination node. Fully adaptive routing is used along both subpaths. The methodology assumes a static fault model and the use of a checkpoint/restart mechanism. However, there are scenarios where the faults cannot be avoided solely by using an intermediate node. Thus, we also provide some extensions to the methodology. Specifically, we propose disabling adaptive routing and/or using misrouting on a per-packet basis. We also propose the use of more than one intermediate node for some paths. The proposed fault-tolerant routing methodology is extensively evaluated in terms of fault tolerance, complexity, and performance.

show abstract

Section: Methodsmentioning

confidence: 99%

A routing methodology for achieving fault tolerance in direct networks

Gomez

Nordbotten

Flich

et al. 2006

IEEE Trans. Comput.

View full text Add to dashboard Cite

show abstract

“…Thus, at least two virtual channels per physical channel (v = 2) are required. In a torus the escape channel also uses the bubble flow control mechanism [4].…”

Section: The Methodologymentioning

confidence: 99%

“…The center node is randomly selected. 4 Notice that with a high number of faults and for a large number of fault combinations, the center node is hardly accessible, as very few links are non-faulty. So, the distance 1 region actually represents a real worst case to access the center node.…”

Section: Fault Analysis Modelsmentioning

confidence: 99%

A Fully Adaptive Fault-Tolerant Routing Methodology Based on Intermediate Nodes

Nordbotten

Gómez

Flich

et al. 2004

Lecture Notes in Computer Science

View full text Add to dashboard Cite

Abstract. Massively parallel computing systems are being built with thousands of nodes. Because of the high number of components, it is critical to keep these systems running even in the presence of failures. Interconnection networks play a key-role in these systems, and this paper proposes a fault-tolerant routing methodology for use in such networks. The methodology supports any minimal routing function (including fully adaptive routing), does not degrade performance in the absence of faults, does not disable any healthy node, and is easy to implement both in meshes and tori. In order to avoid network failures, the methodology uses a simple mechanism: for some source-destination pairs, packets are forwarded to the destination node through a set of intermediate nodes (without being ejected from the network). The methodology is shown to tolerate a large number of faults (e.g., five/nine faults when using two/three intermediate nodes in a 3D torus). Furthermore, the methodology offers a gracious performance degradation: in an 8 × 8 × 8 torus network with 14 faults the throughput is only decreased by 6.49%.

show abstract

“…An extension of virtual cut-through switching, known as Bubble Flow Control (BFC) [5], was successfully proven to avoid deadlock in deterministic tori with virtually no cost. A torus can be seen as a collection of unidimensional rings, which, under DOR, are visited in a specific order.…”

Section: Deadlock Avoidance and Adaptive Routingmentioning

confidence: 99%

On the design of a high-performance adaptive router for CC-NUMA multiprocessors

Puente

Gregorio

Beivide

et al. 2003

IEEE Trans. Parallel Distrib. Syst.

Self Cite

View full text Add to dashboard Cite

Abstract-This work presents the design and evaluation of an adaptive packet router aimed at supporting CC-NUMA traffic. We exploit a simple and efficient packet injection mechanism to avoid deadlock, which leads to a fully adaptive routing by employing only three virtual channels. In addition, we selectively use output buffers for implementing the most utilized virtual paths in order to reduce head-of-line blocking. The careful implementation of these features has resulted in a good trade off between network performance and hardware cost. The outcome of this research is a High-Performance Adaptive Router (HPAR), which adequately balances the needs of parallel applications: minimal network latency at low loads and high throughput at heavy loads. The paper includes an evaluation process in which HPAR is compared with other adaptive routers using FIFO input buffering, with or without additional virtual channels to reduce head-of-line blocking. This evaluation contemplates both the VLSI costs of each router and their performance under synthetic and real application workloads. To make the comparison fair, all the routers use the same efficient deadlock avoidance mechanism. In all the experiments, HPAR exhibited the best response among all the routers tested. The throughput gains ranged from 10 percent to 40 percent in respect to its most direct rival, which employs more hardware resources. Other results shown that HPAR achieves up to 83 percent of its theoretical maximum throughput under random traffic and up to 70 percent when running real applications. Moreover, the observed packet latencies were comparable to those exhibited by simpler routers. Therefore, HPAR can be considered as a suitable candidate to implement packet interchange in next generations of CC-NUMA multiprocessors.

show abstract

A flow control mechanism to avoid message deadlock in k-ary n-cube networks

Cited by 57 publications

References 13 publications

A routing methodology for achieving fault tolerance in direct networks

A routing methodology for achieving fault tolerance in direct networks

A Fully Adaptive Fault-Tolerant Routing Methodology Based on Intermediate Nodes

On the design of a high-performance adaptive router for CC-NUMA multiprocessors

Contact Info

Product

Resources

About