The MPI Tool Interfaces: Past, Present, and Future—Capabilities and Prospects

From the beginning, the MPI standard included a profiling interface that enabled performance tools to intercept MPI calls and record statistics of their use. This still forms the basis for a rich and portable tool environment, which is invaluable for users. The MPI forum has since then expanded its efforts in this area by adding more support for tools, in particular the MPI\(\_\)T interface, and this has also sparked similar efforts in other standards, like OpenMP or OpenACC. In this paper we will highlight the current status of the available interfaces, discuss their gaps and show how the MPI Tools Working Group in the MPI Forum is working on new approaches to close these gaps.