Exploring InfiniBand Congestion Control
Ahmed Yusuf Mahamud · NORA - Norwegian Open Research Archives · 2015
Congestion Control (CC) is used to achieve high performance and good utilization of network resources during high load in lossless interconnection networks. Without CC a congestion which started from a single node can grow, spread and degrade the performance of the network. Congestion can affect both the contributors of the congestion and also other traffic flows in the network. Infiniband (IB) is one of communication standards providing support for Congestion Control. The IB standard describes the CC functionality for detecting and resolving congestion. The behavior of the IB CC mechanism depends on the values of CC parameters. The given values of the parameters will determine characteristics like how aggressive the congestion detection should be, the rate of feedback from the forwarding node detecting congestion to the contributors of the congestion - and how much and for how long the contributors should lower their injection rates. But there are very few guidelines about how to set the values of the CC parameters for IB CC it to be efficient. In this thesis, an experiment of a Mesh network topology will be conducted using OmNet++ as a simulation platform. Large amount of traffic will be generated and fed to the network until a congestion is contributed. The performance will be measured when Infiniband congestion control is disable and when it is enabled. The results from those simulations will be compared and analysed. The topology s host-to-switch link capacities are to be increased. There will be a search for proper IB CC parameters and finally, we will learn more about how IB CC parameters influence performance by focusing on some of the parameters.