High Performance Dense Linear System Solver with Resilience to Multiple Soft Errors

Abstract

In the multi-peta-flop era for supercomputers, the number of computing cores is growing exponentially. However, as integrated circuit technology scales below 65 nm, the critical charge required to flip a gate or a memory cell has been reduced and thus causing higher soft error rate from cosmic-radiations. Soft errors affect computers by producing silently data corruption which is hard to detect and correct. Current research of soft errors resilience for dense linear solver offers limited capability when facing large scale computing systems, and suffers from both soft error and round-off error due to floating point arithmetic. This work proposes a fault tolerant algorithm that recovers the solution of a dense linear system Ax = b from multiple spatial and temporal soft errors. Experimental results on Cray XT5 supercomputer confirm scalable performance of the proposed resilience functionality and negligible overhead in solution recovery.