On Fri, Mar 9, 2012 at 11:39 AM, Justin Talbot <jtal...@cs.stanford.edu> wrote: >> >> Isn't R much like Lisp under the covers? Afterall, it evolved from Scheme. >> Hasn't there been a great deal of work done on optimizing Lisp over the >> last 30 years? This suggests that instead of dropping the R/S semantics >> and moving to another language like Julia, the proposals of Ross Ihaka >> and Duncan Temple Lang could be followed to provide the familiar >> R/S syntax on top of an optimized Lisp engine. >> > > I think R started off as a Lisp-like language, but since adopting S > semantics, it has diverged quite a ways. I think it's better to think > of R as a combination of two languages: a dynamically-typed high-level > language, much like Javascript or Lua, and an array language, like > APL. I think those are the right places to be looking to see how to > make R fast. Fortunately, all three of those languages have had a lot > of performance work done already that R could just steal from > wholesale.
Thanks for the clarification Justin. What about the S4 classes and methods? The design resembles CLOS, and currently this is interpreted R code. Have you addressed performance issues associated with this? What relative impact does this have compared with other optimizations like vectorization? Thanks, Dominick >> Another possibility is to implement R/S on top of an optimized virtual >> machine like the JVM, LLVM, etc. >> > > I like this in theory. But in practice, I'm not sure how well it would > work for R. JVM implementations of dynamic languages, like JRuby and > Jython run marginally faster (30-40%) than their C interpreters. You > do get the Java ecosystem, which is nice, but the performance > improvements probably aren't enough to make it worthwhile. And, of > course, R already has a pretty good Java connection story. > > LLVM is a better option; I know there's another group out there > looking at R on LLVM. But I'll just note that the really high > performance dynamic languages (e.g. Google's V8 implementation of > Javascript and Mike Pall's LuaJIT) are hand-rolled JITs. LLVM-based > implementations of dynamic languages, like Unladen Swallow, have not > been particularly successful. It remains to be seen how well R would > map to LLVM. > > Justin ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
