On Sun, May 30, 2010 at 2:25 PM, Branden Tanga <branden.tanga / gmail.com> wrote:
> In any case, performance tuning an multi threaded application is not
> easy. You might even have to look at alternative runtimes, like running
> it through jruby/tomcat to take advantage of java multi threading
> (assuming that jruby has the appropriate hooks into the jvm to
> accomplish such a thing).

JRuby threads are Java threads, which on all the common JVM
implementations are just OS-level threads. So yes, threaded code in
Ruby running in JRuby actually uses native threads and actually runs
concurrently across cores. For this reason, you can run an entire
Rails site with a single JRuby instance and saturate all your cores in
the process.

- Charlie