From: Lionel Bouton <lionel-subscription@...>
Date: 2008-03-05T01:50:00+09:00
Subject: Re: jruby vs mri memory management

Charles Oliver Nutter wrote:
> Lionel Bouton wrote:
>> - 1.0 was slower than MRI (between 2x and 3x) and 1.1RC2 slightly faster 
>> (5 to 10%), the code was mainly doing floating point computations.
> 
> I did some investigation on the benchmarks.
> 
> - I skipped FRANK because it was already easily 2x as fast as MRI

If you happen to get a similar problem, for the reference DOUG makes 
1.1RC2 crash here.

I couldn't find any download for jruby trunk (nightly builds would
be even nicer than the RCs). I've not much time so I'll just assume
that this was fixed and not a corner case hit in my environment.

> 
> - All the remaining cases showed up as being slower or only slightly 
> faster than MRI, which is very unusual. So I ran a sampling profile and 
> that pointed me toward Struct being slower than it should be. Struct 
> hasn't been updated with many recent optimizations in the rest of the 
> system, and I'm sure it can be made a lot faster.
> 
> I filed a bug: http://jira.codehaus.org/browse/JRUBY-2220
> 

Sorry I didn't have time to submit this on the spot and forgot about it 
later. Glad I could submit this before the final 1.1 and to see that you 
react so quickly.

By the way, I looked at Nailgun and it would indeed be a good fit for my 
requirements. Thanks for the pointer.

I've seen a recent video of Matz presenting Ruby 1.9 to the Google 
people (http://www.youtube.com/watch?v=oEkJvvGEtB4). He spoke of 
alternative Ruby VMs and mentionned that JRuby worked great and now had 
even better performance than MRI in the general case.
I think he made one of the best compliments one could expect from him 
when telling "I've mixed feelings about this" :-)

Lionel