Performance tools for today's HPC: Are we addressing the right issues?

Abstract High-performance computing (HPC) application developers can no longer afford the luxury of programming to just one platform. The usefulness and longevity of software now depend on portability as well as performance. This paper examines the appropriateness of existing tools in developing and tuning applications that must be both efficient and portable. A series of design tradeoffs have been made, with the result that today's tools are slanted toward one goal or the other but do not respond adequately to both. These tradeoffs are explored through a series of examples drawn from current tools. Suggestions are presented for how tools might better support the evolving needs of HPC programmers.