On Gentoo, Ruby with threads is ridiculously slow. Machine is an Xeon
E5320 1.86GHz.

$ ruby-nothreads calculate.rb
55

Ruby 1.8.6 patch 111 on i686-linux
It took 9.759139 seconds to run. 102468 iterations per
second.


$ ruby-threads calculate.rb
55

Ruby 1.8.6 patch 111 on i686-linux
It took 21.473884 seconds to run. 46568 iterations per
second.


>
> Well, on Gentoo you'd need to turn off the "threads" USE flag globally.
> Either everything (in this case Ruby and Tcl/Tk for sure) is with
> "threads" or everything is without it. Personally, on my two UP systems
> (non-SMP) I turn it off and on my dual-core SMP system I turn it on. But
> that's really superstition more than anything based on measurements.
>
> I can't speak for other distros, Windows, Intel vs. AMD, etc. But as far
> as I know on Gentoo it's safe to go "-threads" across the board even on
> an SMP system. I'm going to go ahead and turn it off on the dual-core
> and see what happens -- I'm wrapping up some benchmarking tests this
> weekend so it's a good time to play around with it in a controlled
> environment.
>
>