A comparison of algorithm-based fault tolerance and traditional redundant self-checking for SEU mitigation

The use of an algorithmic, checksum-based "EDAC" (error detection and correction) technique for matrix multiply operations is compared with the more traditional redundant self-checking hardware and retry approach for mitigating single event upset (SEU) or transient errors in soft, radiation tolerant signal processing hardware. Compared with the self-checking approach, the check-sum based EDAC technique offers a number of advantages including lower size, weight, power, and cost. In a manner similar to the SECDED (single error correction/double error detection) EDAC technique commonly used on memory systems, the checksum-based technique can detect and correct errors on the same processing cycle, reducing transient error recovery latency and significantly improving system availability. The paper compares the checksum-based technique with the self-checking technique in terms of failure rates; upset rates coverage, percentage overhead, detection latency, recovery latency, size, weight, power, and cost. The paper also looks at the percentage overhead of the checksum-based technique, which decreases as the size of the matrix increases.