> In my experience with MPI programs, comparing cygwin and linux, > message passing takes longer under cygwin, but the time may be made up > elsewhere, if the compilation is truly similar. > > You mention that considerable time is spent in log(), pow(), exp() > but leave us guessing how you implemented them.
I did not implement them. They are from whatever -lm means on Cygwin. I use them to compute my own formula repeatedly for hundreds of different vectors. > Then you imply that you think cygwin, rather than your math functions, > is the speed determining factor, without giving us a means to judge. They are not mine. There must be a misunderstanding... > The glibc versions of these functions are much faster than the newlib > versions, particularly if you permit the use of <mathinline.h>. > Neither approach the potential of pentium4, but the simplest way to > speed them up on cygwin is to employ something like <mathinline.h>, > and to provide your own pow() (or to use a compiler and library which > targets pentium4). Can this be done with just CFLAGS? I really don't want to pollute my code with ``#ifdef CYGWIN''... Thank you, -mi -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/