Exploring the Effect of Compiler Optimizations on the Reliability of HPC Applications

The strict power efficiency constraints required to achieve exascale systems will dramatically increase the number of detected and undetected transient errors in future high performance computing (HPC) systems. Among the various factors that effect system resiliency, the impact of compiler optimizations on the vulnerability of scientific applications executed on HPC systems has not been widely explored. In this work, we analyze whether and how most common compiler optimizations impact the vulnerability of several mission-critical applications, what are the trade-offs between performance and vulnerability and the causal relations between compiler optimization and application vulnerability. We show that highly-optimized code is generally more vulnerable than unoptimized code. We also show that, while increasing optimization level can drastically improve application performance as expected. However, certain cases of optimization may provide only marginal benefits, but considerably increase application vulnerability.