Thanks (again) Iñaki. There was a typo in my reply above. I should have said: I *can't* answer the question re USE_LOCKING=1.
Those other suggestions are really helpful too; I really didn't understand what the difference was (I'm still not clear what the differences are between say openblas-openmp and openblas-openmp64), but I did get R to pass mgcv's thread safe test with both openblas-openmp and blis-openmp, so I have aliased those options for use too. Just using blis ( /lib64/blisblas/libblas.so.3 ) was generating a segfault when running the mgcv test. Really appreciate the help! All the best G On Wed, 27 May 2020 at 14:09, Iñaki Ucar <iu...@fedoraproject.org> wrote: > > On Wed, 27 May 2020 at 21:40, Gavin Simpson <ucfa...@gmail.com> wrote: > > > > Thanks Iñaki, that is exactly what i was looking for, esp the last > > option which I have now configured as an alias for easy remembering. > > > > I can answer the question re USE_LOCKING=1. I think that using both > > those options is required to get thread-safety even if openblas was > > compiled for single thread use. I don't know to what extent Simon has > > engaged with upstream on this etc. > > I've seen that there is a brief note about this in the project's wiki. > I agree that a sensible default in any distro would be to build > openblas-serial with USE_LOCKING=1. But I don't understand why there > is no recommendation upstream (or I didn't find it besides the note in > the wiki) and there's no idea about the performance penalty that we > incur doing so. I brought this topic to fedora-devel. > > > All I know is that using the openblas shipped with Fedora for R is > > currently a recipe for disaster for the large GAMs we're trying to > > fit. But being able to switch to atlas temporarily is a good > > alternative. > > Note that switching to openblas-openmp (libopenblaso.so) should be > thread-safe and will probably get you a better performance than Atlas. > Also, Fedora packages blis (which provides > /lib64/blisblas/libblas.so.3). It seems to be thread-safe should be > more performant than Atlas too. > > -- > Iñaki Úcar -- Gavin Simpson, PhD [he/him/his] [t] +1 306 337 8863 • Research Scientist [f] +1 306 337 2410 Institute of Environmental [tw] @ucfagls Change & Society [w] goo.gl/Zpkdem University of Regina [w] www.iecs-uregina.ca Regina, SK S4S 0A2, Canada [iD] 0000-0002-9084-8413 • Adjunct Professor, Department of Biology, University of Regina. _______________________________________________ R-SIG-Fedora mailing list R-SIG-Fedora@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-fedora
