Question

The code below aims at making TCP Server and Clients.
But when the number of the client threads is too big(for example: 100 threads), then client receives an “Connection reset by peer” error. I can’t find out the cause of the error, so I need your help.

Server:

#!/usr/bin/env ruby1.9
# -*- coding: utf-8 -*-

require "socket"
crab = TCPServer.new "127.0.0.1", 8087
while browser = crab.accept
  Thread.new browser do | client |
    puts client.gets
    client.puts "hello"
    client.close
  end
end

Client:

#!/usr/bin/env ruby1.9
# -*- coding: utf-8 -*-
require "socket"
threads_arr = []
ARGV[0].to_i.times do    
  t = Thread.new do
    client = TCPSocket.new "127.0.0.1", 8087
    client.puts "hello"
    client.gets
    client.close
  end  
  threads_arr << t
end
threads_arr.each do | t |
  t.join
end

Envrionment:

Mac OS X 10.6.8

ruby 1.8.7p174 / ruby 1.9.2p180

Answer 1

Would this be easier to do in EventMachine? Threading will only scale so far before it starts to cause trouble. EventMachine also handles load better when receiving a large number of connections.

You may need to check that your accept queue is sufficiently large. The default is something like 5 pending connections and if they can’t be acknowledged quickly enough you might have them dropped.