ApproxDup: Developing an Approximate Instruction Duplication Mechanism for Efficient SDC Detection in GPGPUs

Nowadays, selective instruction duplication (SelDup) is the typical approach to detect silent data corruption (SDC) in GPGPU. However, owing to the up-to-billions fault sites of parallel GPGPU kernel functions, it usually introduces tremendous overhead to perform fault injections (FIs) for obtaining the duplication-candidate instruction set (although can be conducted in parallel). Moreover, current SelDup typically considers all SDCs severe and tends to duplicate more instructions. The nontrivial duplication overhead seriously restricts the deployment of current SelDup on resource-constrained systems (e.g., embedded GPGPUs). To address the above challenges, this article proposes an approximate instruction duplication (ApproxDup) mechanism for efficient SDC detection in GPGPUs. First, to replace the expensive FI-based duplication-candidate instructions identified method, we drive out a machine learning (ML)-based model (SDC-predictor) for instructionwise SDC proneness and severity estimation. Our key insight is that instruction type/functionality and instruction dependency set can efficaciously characterize the instructionwise SDC proneness in GPGPUs. In contrast, the instruction's original data magnitude, fault propagation range, and error detected features can distinguish its SDC severity. Second, incorporating the concept of approximate computing, we propose ApproxDup that preferentially duplicates severe-SDC-prone instructions while relaxing the detection of minor/detectable SDCs for traditional SelDup overhead reduction. Experimental results exhibit that ApproxDup can cover 92.51% of severe SDCs while merely increasing 38% of dynamic instructions, which achieves a better tradeoff between reliability and performance compared with the state-of-the-art SelDup. Furthermore, we discuss the effectiveness of the proposed method on different ML models/applications/GPGPU architectures.