[R-sig-hpc] doMC and foreach can not use all cores

[该走了]

Hello evervyone!

When I use doMC and foreach for 'parallel' comupting, I find that R
just open two processes in one core. I have tried many times in
different circumtances, but It never use another core even I
registerDoMC( core = 4 ). Is there anyone meet the similar problem
like me. Hope someone can help me configure why.

In addtion, my system is Fedora15-x86-64bit, R-2.13.1, inter(R)
Core(TM) Duo CPU*2 @2.66Ghz.

Thanks in advance!