> On 21 Aug 2017, at 17:40, Ghislain Durif wrote:
>
> I understand why this is a BLAS related issue and not directly an R related
> issue. Nonetheless, my concern was for non-advanced R users, that may don't
> even know what BLAS is. For instance, I have a package on the CRAN that use
> 'mcla
Hi Ista,
Maybe a little comment in the 'matmult {base}' doc page or on the
'options {base}' in the field 'matprod' would be useful to remind users
to be cautious regarding BLAS multi-threading?
I understand why this is a BLAS related issue and not directly an R
related issue. Nonetheless, my
Hi Ghislain,
The documentation at
https://cran.r-project.org/doc/manuals/r-release/R-admin.html#BLAS
provides a fair bit of information. What specifically would you like
to see added?
Best,
Ista
On Mon, Aug 21, 2017 at 10:13 AM, Ghislain Durif
wrote:
> Hi Tomas,
>
> Thanks for your answer.
>
>
Hi Tomas,
Thanks for your answer.
Indeed, I checked and my R-3.4.1 installed from the ubuntu repository
use 'libopenblasp-r0.2.18.so' while my R-3.3.2 that I did compiled on my
machine use 'libRblas.so' which explain the difference of behavior.
I will use RhpcBLASctl to avoid issue when comb
Many, though not all, threaded BLAS honor the OpenMP environment
variables; you might see whether setting OMP_THEAD_LIMIT or
OMP_NUM_THREADS does what you want.
Best,
luke
On Mon, 21 Aug 2017, Tomas Kalibera wrote:
Hi Ghislain,
I think you might be comparing two versions of R with different
Hi Ghislain,
I think you might be comparing two versions of R with different BLAS
implementations, one that is single threaded (is your 3.3.2 used with
reference blas?) and one that is multi threaded (3.4.1 with openblas).
Could you check with "perf"? E.g. run your benchmark with "perf record"
