Benchmarking the Stack Trace Analysis Tool for BlueGene/L

We present STATBench, an emulator of a scalable, lightweight, and effective tool to help debug extreme-scale parallel applications, the Stack Trace Analysis Tool (STAT). STAT periodically samples stack traces from application processes and organizes the samples into a call graph prex tree that depicts process equivalence classes based on trace similarities. We have de-veloped STATBench which only requires limited resources and yet allows us to evaluate the feasibility of and identify potential roadblocks to deploying STAT on entire large scale systems like the 131,072 processor BlueGene/L (BG/L) at Lawrence Livermore National Laboratory. In this paper, we describe the implementation of STATBench and show how our design strategy is generally useful for emulating tool scaling behavior. We validate STATBench's emulation of STAT by comparing execution results from STATBench with previously collected data from STAT on the same platform. We then use STATBench to emulate STAT on congurations up to the full BG/L system size at this scale, STATBench predicts latencies below three seconds.