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Next: Introduction

Debugging Optimized Parallel Programs

Stephen McLaughry

Fri May 30 15:48:20 PDT 1997


Optimization of data-parallel languages compounds the difficulty of the problem of parallel debugging. While the constrained structure of such languages is intended to simplify the job of the parallel programmer, the loss of flexibility concomitant with this structure often results in programs that, if left unoptimized, would have unacceptably poor performance. The programmer needs a debug tool capable of interacting with an optimized, distributed system and reporting the behavior of such a system in terms of the source code from which it is derived.

We describe some of the obstacles to source-level debugging of optimized data-parallel programs. We present general solutions to these problems, and discuss implementation details. We then describe several example debugging scenarios to demonstrate the capabilities of our prototype system, ZEE (ZPL DEBUGGER).

Steve McLaughry
Fri May 30 15:48:07 PDT 1997