MRNet, the multicast/reduction network, is a software infrastructure for scalable group communication amongst tool components and scalable data analysis operations. It is an open-source software project and has been integrated (in some cases as proofs of concept) into tool projects like the CEPBA-Tools Environment (European Center of Parallelism of Barcelona), DPCL, Open|SpeedShop, Paradyn, Scalasca, STAT (the Stack Trace Analysis Tool) and TAU. We are also in the formative stages of integrations with tool, including TotalView.

We believe that MRNet's flexible, lightweight, tree-based approach makes it the ideal infrastructure component for most distributed tools. The goals of this talk are to summarize MRNet's currently available features and to generate discussion on MRNet's future. Toward the latter goal, we present ongoing and future MRNet developments. We also wish to hear from about features that would make MRNet better suited for your tool development needs or deficiencies of the model/implementation that you believe render it unsuitable.