Disable OpenMP in Eigen #345
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Eigen's OpenMP parallization can lead to wrong results in certain cases likely due to interference with our own parallelization as reported in atmtools#344. Seems to also be compiler dependent since the problem was only reproducable in GCC 9. See also: https://eigen.tuxfamily.org/dox/TopicMultiThreading.html Adding `Eigen::initParallel()` is not enough to solve the issue in atmtools#344. Only setting the number of threads to 1 with `Eigen::setNbThreads(1)` fixes it, therefore disabling OpenMP altogether in Eigen seems the safest solution. Turning OpenMP off in Eigen didn't show any negative performance impact for the test provided in atmtools#344.
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Eigen's OpenMP parallization can lead to wrong results in certain cases likely
due to interference with our own parallelization as reported in #344. Seems to
also be compiler dependent since the problem was only reproducable in GCC 9.
See also:
https://eigen.tuxfamily.org/dox/TopicMultiThreading.html
Adding
Eigen::initParallel()is not enough to solve the issue in #344.Only setting the number of threads to 1 with
Eigen::setNbThreads(1)fixes it, therefore disabling OpenMP altogether in Eigen seems the safest
solution.
Turning OpenMP off in Eigen didn't show any negative performance impact for
the test provided in #344.