New Theory for Deadlock-Free Multicast Routing in Wormhole-Switched Virtual-Channelless Networks-on-Chip

Abstract

Abstract-A new theory for deadlock-free multicast routing especially used for on-chip interconnection network (NoC) is presented in this paper. The NoC router hardware solution that enables the deadlock-free multicast routing without utilizing virtual channels is introduced formally. The special characteristic of the NoC is that, wormhole packets can cut-through at flit-level and can be interleaved in the same channel with other flits of different packets by multiplexing it using a rotating flit-by-flit arbitration. The routing paths of each flit can be guaranteed correct because flits belonging to the same packet are labeled with the same local Id-tag on every communication channel. Hence, multicast deadlock problem can be solved at each router by further applying a hold-release tagging mechanism to control and manage conflicting multicast requests.Index Terms-Network-on-chip, tree-based and multipath-based multicast routing, Id-tag-based wormhole packet switching, runtime adaptive routing and scheduling.

Runtime connection-oriented guaranteed-bandwidth network-on-chip with extra multicast communication service

“…The concept of Hold-Release Tagging Mechanism for Multicast Scheduling Policy can be introduced [13,14,17], which theoretically results in a unique solution for a runtime deadlock-free multicast routing method [15]. The concept of Flexible Runtime Connection-Oriented GuaranteedBandwidth for Quality-of-Service can be introduced, which is explained in this paper, where the switched virtual circuit configuration can be made during application execution time.…”

Planar adaptive network-on-chip supporting deadlock-free and efficient tree-based multicast routing method

“…The work in [8][9][10] have presented the concept and methodology to route multicast messages by using the tree-based method that has been utilized in general internetworking context. The work in [11] has presented a new theory for deadlock free tree-based multicast routing for networks-on-chip area. The theory is developed based on a dynamic local ID-tag routing organization and the concept of a hold-release tagging mechanism.…”

“…The multicast NoC router architecture is designed and implemented based on the novel theory for deadlock-free multicast routing presented in our previous work [11].…”

Supporting efficient collective communication in NoCs

“…Without any special hardware mechanisms, even if 1% of injected packets are multicast, there is a sharp drop in saturation throughput [12]. Recent work proposes efficient multicast routing support to improve NoC performance [1,12,20,26,37,38,39,41].…”

“…sages for the PARSEC benchmarks [3] in a 16-core system 2 . Prior NoC multicast proposals [1,12,20,26,37,38,39,41] implicitly assume several unicast packets will deliver these messages to a single destination; this can lead to redundant network traversals and create transient hotspots in the network. To provide high performance, scalable NoCs should handle traffic in an intelligent fashion by eliminating these redundant messages.…”