From: MenTaLguY <mental@...>
Date: 2008-03-26T03:11:55+09:00
Subject: Re: thread.rb

On Tue, 25 Mar 2008 20:57:48 +0900, "Robert Klemme" <shortcutter@googlemail.com> wrote:
> I opt against using Thread.critical because this is a global exclusive
> lock on all threads and it is unlikely to continue to exist in the
> light of JRuby and others. I'd rather use Mutex#try_lock or Monitor's
> #wait with timeout parameter.

Agreed, anything using Thread.critical is not very future-proof.

Note, however, that while Monitor is okay under JRuby, in MRI (1.9 at least)
it uses Timeout in an uncontrolled way and is not entirely reliable as a
result.  To implement Monitor robustly in JRuby we ended up adding timeout
support to JRuby's ConditionVariable#wait.

*** I would strongly recommend _against_ using any concurrency primitive in
1.9 except for the primitives from thread.rb/thread.so. ***

Given that, the most directly portable way to get a robust queue that
supports timeouts is to roll your own using Mutex, ConditionVariable, and
some safe source of timed events like Scheduler.

-mental