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The present work shows that the \acrfull{iba} enables the transmission of small messages at high rates with sub-microsecond latencies. Together with the presented performance optimizations, the \gls{iba} is eminently suitable as communication technology for applications with hard real-time requirements.
With only a few adaptions to the existing node-type interface and the buffer management of VILLASnode, it was possible to create an \textit{InfiniBand} node-type that makes full use of the \gls{iba}'s zero-copy capabilities and can initiate data transfers without needing system calls. The adaptions that have been made were necessary because complications, which were non-existent with prior node-types, emerged. Eventually, since the InfiniBand Architecture is rooted in the \acrfull{via}, these alterations facilitate VILLASnode with an interface that is---with minimal adaptions---compatible to other \acrshortpl{via} as well.
In the custom benchmark that was used, the InfiniBand node-type showed median latency between approximately \SI{1.7}{\micro\second} (for high rates and small message sizes) and \SI{4.9}{\micro\second} (for low rates and large message sizes). Compared to the \textit{shmem} node-type, which can be seen as zero-latency reference, these median latencies were only roughly 1.5--\SI{2.5}{\micro\second} higher. This is an excellent achievement since the latter solely allows communication between nodes on the same host system. The former, on the other hand, also allows communication between nodes on different host systems. For comparison: prior node-types that allow communication between different host systems and rely on Ethernet as communication technique, showed median latencies which were one order of magnitude larger than the median latencies the \textit{InfiniBand} node-type showed. Furthermore, with the new node-type, much higher transmission rates could be achieved and the latency's predictability substantially improved.
It can thus be concluded that the \textit{InfiniBand} node-type is a valuable extension to the pool of existing VILLASnode node-types. Although the node-type is not suitable for inter-laboratory communication, it enables hard real-time scalability of simulation power within laboratories.