R package that automatically uses several cores?

Question

I have noticed that R only uses one core while executing one of my programs which requires lots of calculations. I would like to take advantage of my multi-core processor to

Answer 1

The easiest way to take advantage of multiprocessors is the multicore package which includes the function mclapply(). mclapply() is a multicore version of lapply(). So any process that can use lapply() can be easily converted to an mclapply() process. However, multicore does not work on Windows. I wrote a blog post about this last year which might be helpful. The package Revolution Analytics created, doSMP, is NOT a multi-threaded version of R. It's effectively a Windows version of multicore.

If your work is embarrassingly parallel, it's a good idea to get comfortable with the lapply() type of structuring. That will give you easy segue into mclapply() and even distributed computing using the same abstraction.

Things get much more difficult for operations that are not "embarrassingly parallel".

[EDIT]

As a side note, Rstudio is getting increasingly popular as a front end for R. I love Rstudio and use it daily. However it needs to be noted that Rstudio does not play nice with Multicore (at least as of Oct 2011... I understand that the RStudio team is going to fix this). This is because Rstudio does some forking behind the scenes and these forks conflict with Multicore's attempts to fork. So if you need Multicore, you can write your code in Rstuido, but run it in a plain-Jane R session.