"Milton Lopez" <[EMAIL PROTECTED]> writes: > I've posted this earlier and have not heard much so far. I'd really > appreciate any guidance on this as we are about to order new hardware. > > We are buying Dell workstations with Red Hat Linux and 64-bit Xeon > CPUs to run R. We could add a second processor to each system, or > buy slightly faster single CPU systems. Is it possible to make a > generalized statement as to what kind of performance improvement we > would see with a single vs. dual processors when running R on these > systems?
Well, if you ask that way, the answer is probably no... It depends on the usage pattern. If you run multiple CPU-bound processes in parallel without too much coordination (parallel make is a good example, simulations another), then you get close to double up from a dual. For a single R process, you can get something like 40% improvement in large linear algebra problems, using a threaded ATLAS. For other problems the speedup is basically nil. There is some potential in threading R or (much easier) some of its vector operations, but that is not even on the drawing board at this stage. Also, these days you might want to consider another factor: noise. Duals tend to be server machines with little emphasis on quietness, where the single-CPU machines have heatpipes and whatnot. -- O__ ---- Peter Dalgaard Øster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
