Deficit Round-Robin (DRR) is a scheduling algorithm that is often used in real-time systems or communication networks for scheduling tasks, or packets. This scheduling algorithm guarantees a share of the bandwidth to each class of traffic, proportional to its assigned quantum. This is an example of bandwidth-sharing policy, as well as other Round-Robin policies like Weighted Round Robin (WRR). Analyzing a bandwidth-sharing policy network requires two steps. The first step is a single-node analysis to compute the service that is guaranteed to each class of traffic. Recent work show that knowing the characteristics of the cross-traffic can improve this guarantee. The second step is a per-class analysis. When all per-node guarantees have been computed, one FIFO network per class can be constructed, and delay bounds can be computed. In this talk, we will show how these two steps are interdependent, especially when the DRR network has cyclic dependencies, and present an iterative scheme that improves both the performance bounds and stability region compared to the state of the art.
Dr. Anne Bouillard, Huawei Technologies, France
Anne Bouillard is since 2020 a researcher at Huawei Technologies, France. Before that she was research engineer at Nokia Bell labs France (2017-2019) and associate professor at ENS Cachan (Brittany location) and ENS in Paris (2006-2017). She received her Phd from École Normale supérieure de Lyon in 2005. Her main research interests are discrete event systems, performance evaluation and probabilities, including network calculus. She is the co-author of a recent book on this topic.