search for: rhpcblasctl

...be possible to work > | round this by creating a small binary wrapper for the rsession binary > | which sets the environment, but it would make a mess of the packaging. > | > | So I've gone with an `/etc/R/Rprofile.site` containing > | > | local({ > | if (require("RhpcBLASctl", quietly=TRUE)) blas_set_num_threads(1) > | }) > | > | which does mean people get this library loaded in all their sessions but > | that doesn't seem to cause any particular trouble (yet). In this case, hook of the / etc / R / Rprofile.site would be best local({ if(require...

...nvironment) don't work. It would probably be possible to work round this by creating a small binary wrapper for the rsession binary which sets the environment, but it would make a mess of the packaging. So I've gone with an `/etc/R/Rprofile.site` containing local({ if (require("RhpcBLASctl", quietly=TRUE)) blas_set_num_threads(1) }) which does mean people get this library loaded in all their sessions but that doesn't seem to cause any particular trouble (yet). Gordon [1]: docs.rstudio.com/ide/server-pro/r-sessions.html > > 2016-08-01 20:06 GMT+09:00 Gordon Ball...

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 combining matrix product and other multi-threading package. Maybe this point regarding multi-threading with BLAS could be added in the R doc. Thanks again, Best, Ghislain Ghislain Durif -------------------------- Research engineer THOTH TEAM INRIA Grenoble Alpes (France)...

...ges that use other multi-threading solutions. Thanks to this stackoverflow question (https://stackoverflow.com/questions/45794290/in-r-how-to-control-multi-threading-in-blas-parallel-matrix-product), I now know that it is possible to control the number of BLAS threads thanks to the package 'RhpcBLASctl'. However, being able to control the number of threads should maybe not require to use an additional package. In addition, the doc 'matmult' does not mention this point, it points to the 'options' doc page and especially the 'matprod' section, in which the multi-thre...

..., but none of them are ideal: * remove OpenBLAS (but even single threaded it performs quite a lot better than the basic libblas) * set OMP_NUM_THREADS globally in people's shells with the system bashrc (but this doesn't work for non-shell, RStudio server sessions) * use a library like RhpcBLASctl to set the number of threads in the global Rprofile * compile a custom openblas with threading disabled, or at least a small default number of threads Any better ideas? Thanks Gordon

...ined? I posted the question on Stackoverflow: https://stackoverflow.com/questions/58886111/r-why-is-matrix-product-slower-when-matrix-has-very-small-values Somebody could reproduce the behavior but I did not get any useful explanations yet. Many thanks for hints! Florian ## disable openMP library(RhpcBLASctl); blas_set_num_threads(1); omp_set_num_threads(1) A <- exp(-as.matrix(dist(expand.grid(1:60, 1:60)))) summary(c(A)) # Min. 1st Qu. Median Mean 3rd Qu. Max. # 0.000000 0.000000 0.000000 0.001738 0.000000 1.000000 B <- exp(-as.matrix(dist(expand.grid(1:60, 1:60)))*10) summary(...

...t; > 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 combining matrix product and > other multi-threading package. > > Maybe this point regarding multi-threading with BLAS could be added in the R > doc. > > Thanks again, > Best, > > Ghislain > > Ghislain Durif > -------------------------- > R...

...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 combining matrix product and >> other multi-threading package. >> >> Maybe this point regarding multi-threading with BLAS could be added in the R >> doc. >> >> Thanks again, >> Best, >> >> Ghislain >> >> Ghislain...

...it will use the reference BLAS which is distributed with R. Section "Linear algebra" of "R Installation and Administration" has details on how to build R with different BLAS/LAPACK implementations. Sadly there is no standard way to specify the number of BLAS worker threads. RhpcBLASctl has specific code for several existing implementations, but R itself does not attempt to control BLAS multi threading in any way. It is expected the user/system administrator will configure their BLAS implementation of choice to use the number of threads they need. A similar problem exists in o...

...t; * remove OpenBLAS (but even single threaded it performs quite a lot > better than the basic libblas) > > * set OMP_NUM_THREADS globally in people's shells with the system > bashrc (but this doesn't work for non-shell, RStudio server sessions) > > * use a library like RhpcBLASctl to set the number of threads in the > global Rprofile > > * compile a custom openblas with threading disabled, or at least a > small default number of threads > > > Any better ideas? > > > Thanks > > Gordon > > _____________________________________________...

...don't work. It would probably be possible to work | round this by creating a small binary wrapper for the rsession binary | which sets the environment, but it would make a mess of the packaging. | | So I've gone with an `/etc/R/Rprofile.site` containing | | local({ | if (require("RhpcBLASctl", quietly=TRUE)) blas_set_num_threads(1) | }) | | which does mean people get this library loaded in all their sessions but | that doesn't seem to cause any particular trouble (yet). I was just working on something that needed environment variables (for automating tests to a database back...

...w: > https://stackoverflow.com/questions/58886111/r-why-is-matrix-product-slower-when-matrix-has-very-small-values > Somebody could reproduce the behavior but I did not get any useful > explanations yet. > > Many thanks for hints! > Florian > > ## disable openMP > library(RhpcBLASctl); blas_set_num_threads(1); omp_set_num_threads(1) > > A <- exp(-as.matrix(dist(expand.grid(1:60, 1:60)))) > summary(c(A)) > # Min. 1st Qu. Median Mean 3rd Qu. Max. > # 0.000000 0.000000 0.000000 0.001738 0.000000 1.000000 > > B <- exp(-as.matrix(dist(expan...

On Friday, 26 June 2020 10.47.13 WEST I?aki Ucar wrote: > I used bcond locally and wrongly assumed that fedpkg build would > support --with BCOND and --without BCOND. Instead, the way to activate > it is to change to "%bcond_with check" and then revert to > "%bcond_without check". The only difference with bootstrap is that > "bootstrap" is recognized