Hi, I wondered about the behavior described in the following stackoverflow question:
https://stackoverflow.com/questions/20674538/mclapply-returns-null-randomly More specifically, I would like to know if you ever considered the suggestion made in the comments of the first answer, namely to somehow warn the user if one of the processes has been killed by the out-of-memory killer ? I am always surprised to see the random NULLs without message/warning/error of any kind, and I think that it could be a useful feature to know whether the function executed by mclapply returned a NULL or if the process was killed for some reason. In the following gist, I have an example of this (in this case non-random) behavior: https://gist.github.com/tvatter/2fcf3a9a99c256f9b9360f596b300715 For the record, I generate the list of NULLs in the 4th mclapply in the girst above with a late 2013 macbook pro with macOS High Sierra, 16GB of memory, and my sessionInfo() is: R version 3.5.0 (2018-04-23) Platform: x86_64-apple-darwin16.7.0 (64-bit) Running under: macOS High Sierra 10.13.6 Matrix products: default BLAS: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib LAPACK: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libLAPACK.dylib locale: [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8 attached base packages: [1] parallel stats graphics grDevices utils datasets methods base loaded via a namespace (and not attached): [1] compiler_3.5.0 tools_3.5.0 yaml_2.1.19 ------------------------------------------------------------ Thibault Vatter Department of Statistics Columbia University [[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
