On Tue, Apr 27, 2010 at 9:09 AM, Dimitry Golubovsky <golubovsky@gmail.com> wrote:

how is the default value of numCapabilities [2]
set when +RTS -N is not on the command line?

Does GHC runtime figure out the number of cores itself,

With 6.12.1 and newer, no "-N" argument implies 1 core, "-Nk" implies k cores, and "-N" without an argument means "use all".