Issue No.04 - July-Aug. (2013 vol.33)
Lukasz G. Szafaryn , University of Virginia
Brett H. Meyer , McGill University
Kevin Skadron , University of Virginia
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/MM.2013.68
As circuit feature sizes shrink, multibit errors become more significant, while previously unprotected combinational logic becomes more vulnerable, requiring a reevaluation of the resiliency design space within a processor core. The authors present Svalinn, a framework that provides comprehensive analysis of multibit error protection overheads to facilitate better architecture-level design choices. Supported protection techniques include hardening, parity, error-correcting code, parity prediction, residue codes, and spatial and temporal redundancy. The overheads of these are characterized via synthesis and, as a case study, presented here in the context of a simple OpenRISC core. The analysis provided by Svalinn shows the difference in protection overheads per component and circuit category in terms of area, delay, and energy. The authors show that the contribution of logic components to the area of a simple core increases from 35 percent to as much as 54 percent with comprehensive multibit error protection. They also observe that the overhead of protection could increase from 29 percent to as much as 97 percent when transitioning from single-bit to multibit protection. Analysis of Svalinn also suggests that storage components will continue to benefit from the use of error-correcting code, whereas products requiring comprehensive coverage of logic components might use redundancy and residue codes. Optimal core-level protection will require novel combinations of these.
Multicore processing, Random access memory, Redundancy, Error correction codes, Logic circuits, multibit error protection, architecture, reliability, Svalinn
Lukasz G. Szafaryn, Brett H. Meyer, Kevin Skadron, "Evaluating Overheads of Multibit Soft-Error Protection in the Processor Core", IEEE Micro, vol.33, no. 4, pp. 56-65, July-Aug. 2013, doi:10.1109/MM.2013.68