Initial studies of networking simulation on COTSon

HP Lab’s COTSon is a full system simulation framework based on AMD’s SimNow. COTSon allows for simulating complete computing systems, ranging from a single node to a large cluster of hundreds of multicore nodes. This technical report is the result of the first six months of the collaboration project between HP Labs and the Universitat Autònoma de Barcelona. The goal of this collaboration is to analyze network simulation in the COTSon environment, in order to propose and implement network topologies. The ultimate goal is to be able to perform reliable and accurate networking simulations using COTSon. This report explains how to configure COTSon to perform a network simulation, and describes the different steps to run a parallel application (NAMD, a molecular dynamics benchmark using MPI) and obtain performance results. The different analysis and results shown in this paper were carried out in 2007, with the versions of COTSon and SimNow available at that moment. Some of the configurations and steps described in this document may have changed since then.