How to make R use all processors?

Question

I have a quad-core laptop running Windows XP, but looking at Task Manager R only ever seems to use one processor at a time. How can I make R use all four processors and spee

Answer 1

On Windows I believe the best way to do this would probably be with foreach and snow as David Smith said.

However, Unix/Linux based systems can compute using multiple processes with the 'multicore' package. It provides a high-level function, 'mclapply', that performs a list comprehension across multiple cores. An advantage of the 'multicore' package is that each processor gets a private copy of the Global Environment that it may modify. Initially, this copy is just a pointer to the Global Environment, making the sharing of variable extremely quick if the Global Environment is treated as read-only.

Rmpi requires that the data be explicitly transferred between R processes instead of working with the 'multicore' closure approach.

-- Dan