Parallel processing in R 2.11 Windows 64-bit using SNOW not quite working

Question

I'm running R 2.11 64-bit on a WinXP64 machine with 8 processors. With R 2.10.1 the following code spawned 6 R processes for parallel processing:

require(foreach)
require(doSNOW)
cl = makeCluster(6, type='SOCK')
registerDoSNOW(cl)
bl2 = foreach(i=icount(length(unqmrno))) %dopar% {
    (Some code here)
}
stopCluster(cl)

When I run the same code in R 2.11 Win64, the 6 R processes are not spawning, and the code hangs. I'm wondering if this is a problem with the port of SNOW to 2.11-64bit, or if any additional code is required on my part. Thanks

BTW, this works just fine on my multicore machine at home running Ubuntu Karmic 64-bit and R 2.11. Unfortunately I have to work on Win64 at work

Answer 1

The code seems to be working here.

R version 2.11.0 (2010-04-22) 
x86_64-pc-mingw32 
other attached packages:
[1] doSNOW_1.0.3    snow_0.3-3      foreach_1.3.0   codetools_0.2-2
[5] iterators_1.0.3
loaded via a namespace (and not attached):
[1] tools_2.11.0

Check your sessionInfo() to make sure your versions match mine. One thing I noted is that on my Windows 7 machine the first attempt to makeCluster made a request for a firewall exception. If you did not explicitly make allowances for the socket communication that could be why it is hanging. The defaults it opened (ugly as it is) was all TCP and UDP ports when operating under the private profile.