Tightening Network Calculus Delay Bounds by Predicting Flow Prolongations in the FIFO Analysis

Abstract

Network calculus offers the means to compute worst-case traversal times based on interpreting a system as a queueing network. A major strength of network calculus is its strict separation of modeling and analysis frameworks. That is, a model is purely descriptive and can be put into multiple different analyses to derive a data flow's worst-case traversal time bound. One of the recent results in this category is the so-called flow prolongation. Flow prolongation actively manipulates the internal model of the analysis by virtually extending the path of flows, i.e., by deliberately creating a more pessimistic setting of resource contention between flows. It was shown that flow prolongation can theoretically decrease worst-case traversal time bounds under certain assumptions. Yet, due to its exhaustive search, it was also shown that flow prolongation does not scale and it might not even have an impact in larger queueing networks. In this paper we introduce DeepFP, an approach to make the analysis scale by predicting flow prolongations using a graph neural network. In our evaluation, we show that DeepFP can improve results in networks of FIFO queues considerably, where the delay bound can be reduced by 13.7% in large FIFO networks at negligible additional cost on the execution time of the analysis.