Highly Scalable Self-Healing Algorithms for High Performance Scientific Computing

Zizhong Chen, Jack Dongarra
2009 IEEE transactions on computers  
As the number of processors in today's high-performance computers continues to grow, the mean-time-to-failure of these computers is becoming significantly shorter than the execution time of many current high-performance computing applications. Although today's architectures are usually robust enough to survive node failures without suffering complete system failure, most of today's high-performance computing applications cannot survive node failures. Therefore, whenever a node fails, all
more » ... ng processes on surviving nodes usually have to be aborted and the whole application has to be restarted. In this paper, we present a framework for building self-healing high-performance numerical computing applications so that they can adapt to node or link failures without aborting themselves. The framework is based on FT-MPI and diskless checkpointing. Our diskless checkpointing uses weighted checksum schemes, a variation of Reed-Solomon erasure codes over floating-point numbers. We introduce several scalable encoding strategies into the existing diskless checkpointing and reduce the overhead to survive k failures in p processes from 2dlog pe:kðð þ 2Þm þ Þ to ð1 þ Oð ffiffi p p ffiffiffi m p ÞÞ 2 :kð þ 2Þm, where is the communication latency, 1 is the network bandwidth between processes, 1 is the rate to perform calculations, and m is the size of local checkpoint per process. When additional checkpoint processors are used, the overhead can be reduced to ð1 þ Oð 1 ffiffiffi m p ÞÞ:kð þ 2Þm, which is independent of the total number of computational processors. The introduced self-healing algorithms are scalable in the sense that the overhead to survive k failures in p processes does not increase as the number of processes p increases. We evaluate the performance overhead of our self-healing approach by using a preconditioned conjugate gradient equation solver as an example. Experimental results demonstrate that our selfhealing scheme can survive multiple simultaneous process failures with low-performance overhead and little numerical impact.
doi:10.1109/tc.2009.42 fatcat:5et7fpfxvrah3jyngwe4zhoj2m