Hi, I've spent a lot of time improving the performance of my 'Matching' package on OS X (as has a generous programmer in the OS X Performance group at Apple). For this package (and it is not alone) there has been a large performance gap between OS X and Linux. Even after many memory and algorithmic optimizations (using BLAS etc), it is still important for performance to not use the default OS X malloc. It starts using the kernel's virtual memory manager for allocations greater than 15kb while the latest version of dmalloc only uses mmap for allocations greater than 256kb.
However, a Linux speed advantage remains which varies with the size of the dataset used. But the performance gap is much greater if the default OS X malloc is used notwithstanding the new algorithm. Therefore, I recommend that R for OS X be linked against dmalloc just as it is for Windows. For details see: http://sekhon.berkeley.edu/macosx/ The memory issue affects a number of packages. For example, the growing number which depend on the very useful Scythe Statistical Library. The latest version of 'Matching' which I've just uploaded to CRAN links against dmalloc (but only when it is built for OS X). A more elegant solution would be for the R OS X build to do so directly. Cheers, Jas. ======================================= Jasjeet S. Sekhon Associate Professor Travers Department of Political Science Survey Research Center UC Berkeley http://sekhon.berkeley.edu/ V: 510-642-9974 F: 617-507-5524 _______________________________________________ R-SIG-Mac mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-mac
