From: Jean-Francois Nadeau <jean-francois.nadeau@...>
Date: 2004-07-06T21:50:40+09:00
Subject: Windows - Socket - Connect - Nonblocking

Hi,

Ruby1.8.1, native ruby (from the pragmatic guys), WinXP.

I am building a very nice Windows RSS aggregator which some of it is written
in Ruby. I really like Ruby because it makes me very productive. Nice work.

In my software, I need to pull the various RSS feeds as fast as I can.
Therefore, I create a thread pool to minimize the network latency of each
feed.

It seemed at first that the IO was not multi-thread enabled because the ruby
process unexpectedly became idle sometimes and after a few seconds, it
started back running.

I decided to investigate the problem by looking at the ruby source code. I
saw that because the thread scheduler works with "select()", there should
not be any blocking in multi-threaded socket IO.

I put some traces in the ruby C code and discovered that the socket connect
call is not nonblocking in Windows.

Here is a ruby snippet to try it:

require 'net/http'

t= Thread.new do
	while 1
		puts "in thread"
	end
end


h = Net::HTTP.new('192.168.0.80', 80)

t.join

Replace 192.168.0.80 with your bogus IP and you will see that "in thread"
messages do not appear while ruby enters Net::HTTP.new.

So, I was wondering if this was a known problem. I have modified the ruby
code to fix that problem but I don't know if my patch is 100% safe. Where
should I send my patch and how?

My patch definitely improves the performance of my code.

Regards,

Jean-Francois Nadeau
http://www.jfnadeau.com