manastech/crystal — pull request #113 by nuisanceofcats (2014-03-18 14:01:44+00:00)
Title: Allow number of threads compiler uses to be configured.

This is useful for me on machines with 2gigabytes or less RAM. In this case when I am able to reduce the number of threads to 4 then the spawned processes no longer consume all of my system memory :)