Fixing a few bugs in JRUBY

I have been fixing the following in JRUBY today:
http://jira.codehaus.org/browse/JRUBY-1230
http://jira.codehaus.org/browse/JRUBY-1228
http://jira.codehaus.org/browse/JRUBY-1108

also, I have supplied patches for some others last week:
http://jira.codehaus.org/browse/JRUBY-1207
http://jira.codehaus.org/browse/JRUBY-1140
http://jira.codehaus.org/browse/JRUBY-1215
http://jira.codehaus.org/browse/JRUBY-1214

and the quite complicated on java threading:
http://jira.codehaus.org/browse/JRUBY-1157

I hope to be able to fix a few more in the next few days, while traveling to San Francisco.

My goal is to help John getting OpenWFEru to run at full speed on JRuby.
The OpenWFEru test suite has a few more quirks remaining, but it’s looking good.

Can’t wait to see this happening.

Faster ruby(2)

Coming back to my previous post (and Charles’s comments!), I went and found my original test on those ruby constants.

Here are the results on ruby (1.8.6):

• WithConstants(N=5000000): 5.94s
• WithoutConstants(N=5000000): 5.33s

Here are the results on jruby:

• WithConstants(N=5000000): 34.15s
• WithoutConstants(N=5000000): 27.47s

So my previous post was wrong, the same behavior appears on both ruby and jruby, and it looks like this is really worth the modification when running on jruby. Those are solely empiric results. I hope I can profile the jruby code and find the differences between the two tests and see from where comes the recorded time difference.

Updated:

Same tests again, with the options provided by Charles (-O -J-server -J-Djruby.jit.threshold=0):

• WithConstants(N=5000000): 11.10s
• WithoutConstants(N=5000000): 8.4s

Woah. That is really speeding things up!

Faster ruby

After reading a post on symbols, I went on doing my own experiment. Here’s what came out:

h[:cool] = :hello

will execute approximately 2 times as fast as:

h["cool"] = :hello

The original post pointed out that symbols are never garbage collected but given the low memory footprint of Ruby, might as well get the extra speed.

An other experiment I did some time ago, if you declare:

module Niko MY_CONST = “this is a string for testing” end

and then try to access it:

Niko::MY_CONST

will be slightly slower than doing:

include Niko MY_CONST

Amusingly enough, this appears to be untrue on jruby. (confirmed that the same behavior is on both plateform, see next post)

Textmate cheats

Might as well learn this one real fast. railstextmatecheats.pdf

Tracing calls in ruby

This simple ruby method will trace every single call of the block given to the trace method.
For more complex things, the unroller gem can also be used.

Switching between JVM on OSX

I wrote a little ruby script to switch the JVM on OSX. Nothing fancy, but this is saving quite some time when testing and debugging.