Comparing performance profiles from two runs is an essential performance analysis step that users routinely perform. In this
work we present
eGprof, a tool that facilitates these comparisons through differential profiling inside
gprof. We chose this approach, rather than designing a new tool, since
gprof is one of the few performance analysis tools accepted and used by a large community of users.
eGprof allows users to ”subtract” two performance profiles directly. It also includes callgraph visualization to highlight the differences
in graphical form. Along with the design of this tool, we present several case studies that show how eGprof can be used to find and to study the differences of two application executions quickly and hence can aid the user in this
most common step in performance analysis. We do this without requiring major changes on the side of the user, the most important
factor in guaranteeing the adoption of our tool by code teams.
This work was performed under the auspices of the U.S. Department of Energy by University of California Lawrence Livermore
National Laboratory under contract No. W-7405-Eng-48 (UCRL-CONF-227812).