From: Charles Oliver Nutter <charles.nutter@...>
Date: 2007-11-23T18:05:31+09:00
Subject: Re: Emulating a Groovy feature?

Luke Melia wrote:
> On Nov 21, 2007, at 2:47 PM, thefed wrote:
> 
>> Begin-Rescue-End blocks tend to slow things down significantly - does 
>> JUST including rescue also take those penalties to speed?
> 
> Sebastian Delmont did some benchmarking on this last year.
> 
> http://www.notsostupid.com/blog/2006/08/31/the-price-of-a-rescue/
> 
> His conclusions: "Using rescue is not much more expensive than running 
> naked. In my tests in particular, it never was more than 5% slower. It 
> might even be cheaper than multiple tests."

It slows down JRuby a bit more than Ruby 1.8, unfortunately, because of 
the way the JVM manages exception handling and operand stacks. But 
generally you won't notice it, since nontrivial code bodies will be 
quite a bit faster than 1.8.

~/NetBeansProjects/jruby-current $ jruby -J-server test.rb
              user     system      total        real
plain    0.493000   0.000000   0.493000 (  0.493000)
plain    0.474000   0.000000   0.474000 (  0.474000)
plain    0.222000   0.000000   0.222000 (  0.222000)
plain    0.220000   0.000000   0.220000 (  0.220000)
plain    0.219000   0.000000   0.219000 (  0.219000)
safe     0.431000   0.000000   0.431000 (  0.431000)
safe     0.338000   0.000000   0.338000 (  0.337000)
safe     0.320000   0.000000   0.320000 (  0.320000)
safe     0.317000   0.000000   0.317000 (  0.316000)
safe     0.319000   0.000000   0.319000 (  0.319000)
rescue   0.315000   0.000000   0.315000 (  0.315000)
rescue   0.313000   0.000000   0.313000 (  0.313000)
rescue   0.314000   0.000000   0.314000 (  0.314000)
rescue   0.312000   0.000000   0.312000 (  0.312000)
rescue   0.312000   0.000000   0.312000 (  0.313000)
~/NetBeansProjects/jruby-current $ ruby test.rb
              user     system      total        real
plain    0.210000   0.000000   0.210000 (  0.214133)
plain    0.210000   0.000000   0.210000 (  0.228721)
plain    0.200000   0.000000   0.200000 (  0.206997)
plain    0.210000   0.000000   0.210000 (  0.206290)
plain    0.200000   0.010000   0.210000 (  0.205982)
safe     0.240000   0.000000   0.240000 (  0.238373)
safe     0.230000   0.000000   0.230000 (  0.243327)
safe     0.240000   0.000000   0.240000 (  0.237573)
safe     0.230000   0.000000   0.230000 (  0.242121)
safe     0.240000   0.000000   0.240000 (  0.237385)
rescue   0.230000   0.000000   0.230000 (  0.238207)
rescue   0.230000   0.000000   0.230000 (  0.235387)
rescue   0.230000   0.000000   0.230000 (  0.234333)
rescue   0.240000   0.000000   0.240000 (  0.234938)
rescue   0.230000   0.000000   0.230000 (  0.240186)

- Charlie