SASSIFI: Evaluating Resilience of GPU Applications

As GPUs become more pervasive in both scalable high-performance computing systems and safety-critical embedded systems, evaluating and analyzing their resilience will grow increasingly important. As soft errors, such as those caused by high-energy particle strikes, form an important fraction of in-field hardware errors, GPU designers must develop tools and techniques to understand the effect of these soft errors on applications. This paper presents an error injection-based methodology to study the soft-error resilience of massively parallel applications running on state-of-the-art NVIDIA GPUs. Our approach uses a low-level assembly-language instrumentation tool called SASSI to profile and inject errors. SASSI provides efficiency by allowing instrumentation code to execute entirely on the GPU and provides the ability to inject into condition code and predicate registers, in addition to general-purpose registers and GPU memory. This paper describes our error injection tool and presents some experiments to illustrate some possible lines of analysis. We injected errors into Rodinia benchmark applications and provide results from those experiments showing average detected and silent error probabilities for applications, static kernels, and dynamic kernel invocations. For applications with multiple invocations of the same static kernel, we also show how our tool can be used to study error propagation as a function of the injection time. We also study the effect of errors on condition code and predicate registers.