Use resolv-replace so slow DNS lookups don't slow or halt Sidekiq

Changes.md

@@ -1,3 +1,11 @@
+2.16.0
+-----------
+
+- Use Ruby's `resolv-replace` to enable pure Ruby DNS lookups.
+  This ensures that any DNS resolution that takes place in worker
+  threads won't lock up the entire VM on MRI.
+  See this [blog post](http://coderrr.wordpress.com/2007/12/06/backgrounding-tasks-in-rails-with-threads-and-using-resolv-replace-to-make-them-faster/) for more info.
+
 2.15.2
 -----------
 

lib/sidekiq/cli.rb

@@ -1,5 +1,6 @@
 $stdout.sync = true
 
+require 'resolv-replace'
 require 'yaml'
 require 'singleton'
 require 'optparse'

lib/sidekiq/version.rb

@@ -1,3 +1,3 @@
 module Sidekiq
-  VERSION = "2.15.2"
+  VERSION = "2.16.0"
 end