Conference paper
Static Routing in Symmetric Real-Time Network-on-Chips
With the rising number of cores on a single chip the question on how to organize the communication among those cores becomes more and more relevant. A common solution is to use a network-on-chip (NoC) that provides communication bandwidth, routing, and arbitration among the cores. The use of NoCs in real-time systems is problematic, since the shared network and all cores connected to it have to be analyzed to derive time bounds of real-time tasks.
We propose to use a statically scheduled, time-division-multiplexed NoC design that allows a decoupled analysis of individual real-time tasks. Our network provides virtual circuits between all cores. These virtual circuits are implemented by delivering messages periodically on a static, fixed routing schedule.
Since the routing does not change, it can be pre-computed offline. This work focuses on the computation of routing schedules for symmetric NoC topologies, e.g., torus and hyper-cube. Due to the symmetry, the all-to-all communication can be modeled via simplified communication patterns that are concurrently processed by all routers.
The scheduling problem is solved by a heuristic that tries to maximize the overlap of active patterns. Our experiments show that, for larger networks, our heuristic yields schedule lengths that are only 15% to 20% longer than theoretical lower bounds.
Language: | English |
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Publisher: | Association for Computing Machinery |
Year: | 2012 |
Pages: | 61-70 |
Proceedings: | 20th International Conference on Real-Time and Network Systems (RTNS 2012) |
ISBN: | 1450314090 and 9781450314091 |
Types: | Conference paper |
DOI: | 10.1145/2392987.2392995 |
ORCIDs: | Schoeberl, Martin |