I have similar problem with CPU bound program of mine on Cygwin too. The difference is something like 35 minutes versus 400 seconds on the same machine but under FreeBSD.
Somebody mentioned that malloc implementation could be the problem. Dunno. I has also crossed my mind that another difference between FreeBSD and Cygwin is implementation of C++ exceptions. Maybe the SJLJ implementation that Cygwin AFAIK uses has too big overhead. VH PS: I think that cgf should really try to improve his PR skills. -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/