On the performance of broadcast algorithms in interconnection networks

Broadcast Communication is among the most primitive collective capabilities of any message passing network. Broadcast algorithms for the mesh have been widely reported in the literature. However, most existing algorithms have been studied within limited conditions, such as light traffic load and fixed network sizes. In other words, most of these algorithms have not been studied at different Quality of Service (QoS) levels. In contrast, this study examines the broadcast operation, taking into account the scalability, parallelism, a wide range of traffic loads through the propagation of broadcast messages. To the best of our knowledge, this study is the first to consider the issue of broadcast latency at both the network and node levels across different traffic loads. Results are shown from a comparative analysis confirming that the coded-path based broadcast algorithms exhibit superior performance characteristics over some existing algorithms

A new scalable broadcast algorithm for multiport meshes with minimum communication steps

Many broadcast algorithms have been proposed for the mesh in the literature. However, most of these algorithms do not exhibit good scalability properties as the network size increases. As a consequence, most existing broadcast algorithms cannot support real-world parallel applications that require large-scale system sizes due to their high computational demands. Motivated by this observation, this paper makes two contributions. Firstly, in an effort to minimise the effects of network size on communication performance, this study proposes a new routing approach that enables the development of efficient broadcast algorithms that can maintain good performance levels for various mesh sizes. Secondly, based on the new routing approach, we propose a new adaptive broadcast algorithm for the mesh. The main feature of the proposed algorithm is its ability to handle broadcast operations with a fixed number of message-passing steps irrespective of the network size. Results from extensive comparative analysis reveal that our algorithm exhibits superior performance characteristics over those of the well-known Recursive Doubling and Extending Dominating Node algorithms

Towards scalable collective communication for multicomputer interconnection networks

A considerable number of broadcast algorithms have been proposed for the mesh over the past decade. Nonetheless, most of these algorithms do not exhibit good scalability properties as the network size increases. As a consequence, most existing broadcast algorithms cannot efficiently support real-world parallel applications that require large-scale system sizes due to their high computational demands. Motivated by these observations, this paper proposes the Nearest Side First Algorithm (or NSF for short) as a new adaptive broadcast algorithm for the mesh. One of the key results is that the performance of the NSF algorithm scales up well with the increase of processing elements, a feature not demonstrated by any previous broadcast algorithms, which enables the proposed algorithm to utilise massive parallel architectures with maximum effectiveness