A Skeletal-Based Approach for the Development of Fault-Tolerant SPMD Applications

Distributing applications over PC clusters to speed-up or size-up the execution is now commonplace. Yet efficiently tolerating faults of these systems is a major issue. To ease the addition of checkpoint-based fault tolerance at the application level, we introduce a {em Model for Low-Overhead Tolerance of Faults}(MoLOToF) which is based on structuring applications using {em fault-tolerant skeletons}. MoLOToF also encourages collaborations with the programmer and the execution environment. The skeletons are adapted to specific parallelization paradigms and yield what can be called {em fault-tolerant algorithmic skeletons}. The application of MoLOToF to the SPMD parallelization paradigm results in our proposed FT-SPMD framework. Experiments show that the complexity for developing an application is small and the use of the framework has a small impact on performance. Comparisons with existing system-level checkpoint solutions, namely LAM/MPI and DMTCP, point out that FT-SPMD has a lower runtime overhead while being more robust when a higher level of fault tolerance is required.