From: "Bartosz Dziewoński" <matma.rex@...>
Date: 2011-08-23T01:57:22+09:00
Subject: Re: Multithreading in Ruby

2011/8/22 Nabs Kahn <nabusman@gmail.com>:
>  rank_page_extract = Thread.new do
>    while rank_pages_download.alive?
>      rank_page = rank_pages_queue.pop
>      items_queue << get_rank_name_url(rank_page)
>    end
>  end

All threads will be started at the same time, so when this runs for
the first time, rank_pages_queue will still be ampty and the next line
will probably raise an exception - which will silently disappear, as
exceptions always do in threads. When debugging a threading program,
always use Thread.abort_on_exception = true - this will generate the
stack trace and barf every time a thread raises an exception.