Sorry fort he late reply, your mail ended up in my spam and I've just seen it recently.
> Does the behaviour change if you temporarily move away > /usr/local/lib/libomp.dylib? It does not change the behavior after loading (or attaching) data.table using "library(data.table)". It is still loaded with multiple threads: "data.table 1.15.4 using 4 threads (see ?getDTthreads). Latest news: r-datatable.com" It does however make it impossible to install data.table from source with these flags (set in ~/.R/Makevars; I also temporarily removed the omp files from /usr/local/include that are bundled in the tarball) """ CPPFLAGS += -Xclang -fopenmp LDFLAGS += -lomp """ This is the error that happens then: """ ... In file included from ./data.table.h:1: ./myomp.h:2:12: fatal error: 'omp.h' file not found #include <omp.h> ^~~~~~~ 1 error generated. make: *** [assign.o] Error 1 ERROR: compilation failed for package ‘data.table’ * removing ‘/Library/Frameworks/R.framework/Versions/4.3-arm64/Resources/library/data.table’ * restoring previous ‘/Library/Frameworks/R.framework/Versions/4.3-arm64/Resources/library/data.table’ Warning in install.packages : installation of package ‘data.table’ had non-zero exit status """ So, the libomp.dylib does indeed seem to be necessary for installing from source with OpenMP support, but not for executing the code > When you reproduce the crash, what does the backtrace say? I haven't done that yet, since I was on the non-OpenMP version right now. I'll come back to you once I tried. Thanks, Philipp Am 08.04.24, 11:13 schrieb "Ivan Krylov" <ikry...@disroot.org <mailto:ikry...@disroot.org>>: В Mon, 8 Apr 2024 10:29:53 +0200 gernophil--- via R-help <r-help@r-project.org <mailto:r-help@r-project.org>> пишет: > I have some weird issue with using multithreaded data.table in macOS > and I am trying to figure out, if it’s connected to my libomp.dylib. > I started using libomp as stated here: > https://mac.r-project.org/openmp/ > <https://mac.r-project.org/openmp/[https://mac.r-project.org/openmp/]> Does the behaviour change if you temporarily move away /usr/local/lib/libomp.dylib? > P.S.: If you need some more details about the actual issue with > data.table you can also check here > (https://github.com/rstudio/rstudio/issues/14517[https://github.com/rstudio/rstudio/issues/14517] > > <https://github.com/rstudio/rstudio/issues/14517[https://github.com/rstudio/rstudio/issues/14517]>) > and here > (https://github.com/Rdatatable/data.table/issues/5957[https://github.com/Rdatatable/data.table/issues/5957] > > <https://github.com/Rdatatable/data.table/issues/5957[https://github.com/Rdatatable/data.table/issues/5957]>) The debugger may be able to shed more light on the problem than just "yes, this is due to OpenMP": https://github.com/rstudio/rstudio/issues/14517#issuecomment-2040231196[https://github.com/rstudio/rstudio/issues/14517#issuecomment-2040231196] <https://github.com/rstudio/rstudio/issues/14517#issuecomment-2040231196[https://github.com/rstudio/rstudio/issues/14517#issuecomment-2040231196]> When you reproduce the crash, what does the backtrace say? -- Best regards, Ivan ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
