[R-pkg-devel] Setting OpenMP threads (globally) for an R package

[Iñaki Ucar]

On Fri, 18 Mar 2022 at 06:33, Simon Urbanek <simon.urbanek using r-project.org> wrote:
>
> > On Mar 18, 2022, at 6:10 PM, Evan Biederstedt <evan.biederstedt using gmail.com> wrote:
> > There is some connection to setting  `export OMP_NUM_THREADS=1` before starting R, and moderate memory usage; that's all I know.
>
> That's odd. OpenMP itself doesn't allocate memory, so that's why I said it shouldn't be related.

Evan didn't share the sessionInfo() output, so my guess is that the
threaded version of OpenBLAS is being used, and, oddly enough, this
honours OMP flags. See https://github.com/xianyi/OpenBLAS/issues/2985

-- 
Iñaki Úcar