From: Roger Pack <rogerpack2005@...>
Date: 2008-12-04T08:44:29+09:00
Subject: [ruby-core:20275] Re: autoload and concurrency

On Tue, Dec 2, 2008 at 11:10 PM, Charles Oliver Nutter
<charles.nutter@sun.com> wrote:
> Require could be made safe if only one thread were allowed to execute
> requires at a time, globally. Whether that's a reasonable tradeoff, I'm not
> sure.
>
> All things are possible...but many require behavioral changes to Ruby.
>
> - Charlie

That might be a great idea.  The only drawback being if you have
file2.rb:
  sleep

run this:

Thread.new { sleep 1; require 'file1'}
require 'file2'

So if one thread is "happily running" within a require file [rails
does this?] then other threads would be prohibited from requiring.

Or I guess it could be mutex-ified per autoload [like require is
currently for 1.9]--i.e. when a second thread loads the same constant,
have it wait till the first's auto-load returns [somewhat of a
band-aid, but...hmm this is hard].

-=R