From: Charles Oliver Nutter <charles.nutter@...>
Date: 2008-07-03T22:51:51+09:00
Subject: Re: Threads and Ruby

Robert Klemme wrote:
> 2008/7/3 Charles Oliver Nutter <charles.nutter@sun.com>:
>> Actually, it's probably more of a stepping stone toward full native,
>> parallel threads.
> 
> That's what I believe, too.
> 
>> And green threads are no faster than regular threads, but are often cheaper
>> to create.
> 
> But these days overhead of OS thread creation is negligible.  I did
> some tests with a Java 6 JVM some time ago and thread creation is
> extremely fast - at least on my Windows XP box. :-)

It's fast, but it's not nothing...JRuby has a thread pool option 
(-J-Djruby.thread.pool.enabled=true) that improves thread-spin-up quite 
a bit. The remaining cost is just because we have heavier in-memory 
structures per-thread than CRuby does, mostly for performance reasons.

Eventually I'd like to trim that down, so that pooled threads results in 
almost free thread spin-up.

- Charlie