Introduction

MALP is a profiling tool for MPI applications based on a multi-agent architecture.

With MALP, MPI applications are launched in a controled environment which adds analysers to collect and process performance data in order to generate measurements reports.

The environment is set up at run time which allows to profile existing MPI applications without modifications.

The classical instrumentation for profiling is to write traces to a file during the execution. The problem here is that the filesystem is a dramatic bottleneck and slows down the execution. Coupling the MPI instrumented application with a MPI analyzer permits to get rid of a this kind of bottleneck by running an analyzer MPI program and one instrumented MPI program.

MALP introduces instrumentation that is separated from analysis and allows the analyzer tool to work on data from instrumentation with quite low overhead.

• The instrumentation sends data to the analyzer (non blocking calls)
• The Analyzer retreives data and processes it

It allows the analyzer not to slow down the profiled application.