Title: Designing scrubbing strategy for memories suffering MCUs through the selection of optimal interleaving distance

Authors: Wei Zhou; Hong Zhang; Hui Wang; Yun Wang

Addresses: School of Computer and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China ' School of Computer and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China ' Department of Computer Science and Engineering, Southeast University, Bangladesh; Key Laboratory of Computer Network and Information Integration, MOE, Nanjing, 210096, China ' Department of Computer Science and Engineering, Southeast University, Bangladesh; Key Laboratory of Computer Network and Information Integration, MOE, Nanjing, 210096, China

Abstract: As technology scales, multiple cell upsets (MCUs) have shown prominent effect, thus affecting the reliability of memory to a great extent. Ideally, the interleaving distance (ID) should be chosen as the maximum expected MCU size. In order to mitigate MCU errors, interleaving schemes together with single error correction (SEC) codes can be used to provide the greatest protection. In this paper, we propose the use of scrubbing sequences to improve memory reliability. The key idea is to exploit the locality of the errors caused by a MCU to make scrubbing more efficient. The single error correction, double error detection, and double adjacent error correction (SEC-DEDDAEC) codes have also been used. A procedure is presented to determine a scrubbing sequence that maximises reliability. An algorithm of scrubbing strategy, which keeps the area overhead and complexity as low as possible without compromising memory reliability, is proposed for the optimal interleaving distance, which should be maximised under some conditions. The approach is further applied to a case study and results show a significant increase in the mean time to failure (MTTF) compared with traditional scrubbing.

Keywords: interleaving distance; memory; multiple cell upsets; MCUs; soft error; reliability; scrubbing; radiation.

DOI: 10.1504/IJCSE.2019.099639

International Journal of Computational Science and Engineering, 2019 Vol.19 No.1, pp.53 - 63

Received: 20 Aug 2016
Accepted: 06 Oct 2016
Published online: 20 May 2019 *

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