From: Robert Feldt <feldt@...>
Date: 2000-10-22T13:06:32+09:00
Subject: [ruby-talk:5747] Q on Queue

Hi,

I just started looking at Ruby's thread support so I might be missing
something vital but:

* In Queue#push:

  1  def push(obj)
  2   Thread.critical = true
  3   @que.push obj
  4   begin
  5    t = @waiting.shift
  6    t.wakeup if t
  7   rescue ThreadError
  8    retry
  9   ensure
  10   Thread.critical = false
  11  end
  12  t.run if t
  13 end

does anything prevent the scheduler from scheduling a thread t2 that are
waiting after t1 (that have been waked up and is about to be run) so that
it gets the next object in the queue before t1?

That is:
@waiting = [t1,t2]
push o1 wakes up t1
interrupted at line 11
push o2 wakes up t2
t2 pops o1
t1 pops o2

Regards,

Robert