JRuby

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: JRuby 1.1
• Fix Version/s: JRuby 1.1.2
• Component/s: Core Classes/Modules
• Labels:

  None
• Environment:

  Latest JRuby 1.1 from trunk.

The following example:

require 'drb'

5.times {
  DRb.start_service('druby://localhost:9001')
  DRb.stop_service
}

Produces the following exception in JRuby:
/opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:865:in `new': Address already in use - Address in use (Errno::EADDRINUSE)
from /opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:865:in `open'
from /opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:865:in `open_server'
from /opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:759:in `open_server'
from /opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:757:in `each'
from /opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:757:in `open_server'
from /opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:1339:in `initialize'
from /opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:1628:in `new'
from /opt/work/jruby.git/lib/ruby/1.8/drb/drb.rb:1628:in `start_service'
from test-drb.rb:4
from test-drb.rb:3:in `times'
from test-drb.rb:3

After some investigation it seems that the flaw is in the DRb itself, and simple
addition of sleep 1 in lib/ruby/1.8/drb/drb.rb, in method run (line 1428), leads to the same exception even in MRI.

Basically, a new Thread is being started in the run method, it has begin-ensure block, but in case when a thread is started but not yet entered begin-ensure, an attempt to stop the service and to kill the thread leads to situation when ensure block is not executed, and the following satement is not being run: @protocol.close if @protocol

Hence, the port is not being freed.

This leads to some rubyspec failures, since the specs exhibit exactly this behavior, starting and stopping the DRb service quickly.

• Assignee:

  MenTaLguY

  Reporter:

  Vladimir Sizikov

• Created:

  31/Mar/08 11:25 AM

  Updated:

  04/Jul/08 9:07 AM

  Resolved:

  03/May/08 10:53 PM