On Mon, Sep 7, 2009 at 4:47 PM, Andrew Piskorski<a...@piskorski.com> wrote: > On Sat, Sep 05, 2009 at 08:31:18PM +0200, Peter Juhasz wrote: > >> I don't understand how is this possible. Maybe there is an issue of >> thread-safety with the R backend, meaning that the two R *interpreter* >> instances are talking to the same backend that's capable of processing >> only one thing at a time? > > No. Particularly since there is no R "backend" involved at all, not > if you're starting up the standard R from Ubuntu 9.04 (rather than > Rserve or something else unusual). People run multiple R processes > concurrently on the same (multi-core) machine all the time, works > fine. > >> Please see http://www.perlmonks.org/?node_id=792460 for an extended >> discussion of the problem, and especially >> http://www.perlmonks.org/?node_id=793506 for excerpts of output and >> actual code. > > The most likely explanation seems to be that you have a bug in your > Perl code. Have you tried using your Perl framework to fork something > OTHER than R? Have you tried manually starting up two R processes and > running your R code that way? And, what is the actual R code you're > running? You don't seem to have shown it anywhere. > > -- > Andrew Piskorski <a...@piskorski.com> > http://www.piskorski.com/ >
Actually, I have ran some tests that clarified the issue somewhat. - It is always possible that my Perl code is buggy but that doesn't seem to play a role in this case. - I tried to use my Perl system to start two non-R processes - it worked as expected, they ran concurrently without ill effects. But please see http://www.perlmonks.org/index.pl?node_id=793907 , where I posted my R code in its simplest form along with an example run which exhibits the symptoms I originally wrote about. >From that test I conclude that it is not my Perl code nor R itself that is wrong here, but the specific package I use. That package - NADA, from which I use the 'cenros' command - seems to be the culprit. Please forgive my complete lack of experience when it comes to R, this made me assume things that didn't make sense. Péter Juhász ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
