Blue Gene/L performance tools

performance tools X. Martorell N. Smeds R. Walkup J. R. Brunheroto G. Almási J. A. Gunnels L. DeRose J. Labarta F. Escalé J. Giménez H. Servat J. E. Moreira Good performance monitoring is the basis of modern performance analysis tools for application optimization. We are providing a variety of such performance analysis tools for the new Blue Genet/L supercomputer. Those tools can be divided into two categories: single-node performance tools and multinode performance tools. From a single-node perspective, we provide standard interfaces and libraries, such as PAPI and libHPM, that provide access to the hardware performance counters for applications running on the Blue Gene/L compute nodes. From a multinode perspective, we focus on tools that analyze Message Passing Interface (MPI) behavior. Those tools work by first collecting message-passing trace data when a program runs. The trace data is then used by graphical interface tools that analyze the behavior of applications. Using the current prototype tools, we demonstrate their usefulness and applicability with case studies of application optimization.