Automated application robustification based on outlier detection

Abstract

In this thesis, we propose automated algorithmic error resilience based on outlier detection. Our approach employs metric functions that normally produce metric values according to a designed distribution or behavior and produce outlier values (i.e., values that do not conform to the designed distribution or behavior) when computations are affected by errors. Thus, for our robust algorithms, error detection becomes equivalent to outlier detection. Our error resilient algorithms use outlier detection not only to detect errors, but also to aid in reducing the amount of redundancy required to produce correct results when errors are detected. Our error-resilient algorithms incur significantly lower overhead than traditional hardware and software error resilience techniques. Also, compared to previous approaches to application-based error resilience, our approaches parameterize the robustification process, making it easy to automatically transform large classes of applications into robust applications with the use of parser-based tools and minimal programmer effort. We demonstrate the use of automated error resilience based on outlier detection for two important classes of applications, namely, structured grid and dynamic programming problems, leveraging the flexibility of algorithmic error resilience to achieve improved application robustness and lower overhead compared to previous error resilience approaches.