Estimation of Round-off Errors in OpenMP Codes

International audienceIt is crucial to control round-off error propagation in numerical simulations, because they can significantly affect computed results, especially in parallel codes like OpenMP ones. In this paper, we present a new version of the CADNA library that enables the numerical validation of OpenMP codes. With a reasonable cost in terms of execution time, it enables one to estimate which digits in computed results are affected by round-off errors and to detect numerical instabilities that may occur during the execution. The interest of this new OpenMP-enabled CADNA version is shown on various applications, along with performance results on multi-core and many-core (Intel Xeon Phi) architectures