From 8d4bc84a8a5a04139905552a145fc7963451f4bb Mon Sep 17 00:00:00 2001
From: Cameron Eagans <me@cweagans.net>
Date: Wed, 16 Sep 2015 11:40:23 -0600
Subject: [PATCH] Use the kvm paravirt provider if Virtualbox >= 5.0.0

---
 README.md   | 1 +
 Vagrantfile | 9 +++++++++
 2 files changed, 10 insertions(+)

diff --git a/README.md b/README.md
index e886431..9c65cc1 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,7 @@ Before launching your Dashbrew environment, you must install VirtualBox and Vagr
 
 * [Vagrant >= 1.6.5](http://www.vagrantup.com/)
 * [VirtualBox 4.3.x](https://www.virtualbox.org/)
+	* Note that installing Virtualbox 5.x is *strongly* recommended for better performance.
 * [Vagrant Hosts Provisioner plugin](https://github.com/mdkholy/vagrant-hosts-provisioner) for managing the /etc/hosts file of both the host and guest machines.
 	* ``$ vagrant plugin install vagrant-hosts-provisioner``
 
diff --git a/Vagrantfile b/Vagrantfile
index e5e47a2..b60339f 100644
--- a/Vagrantfile
+++ b/Vagrantfile
@@ -29,6 +29,15 @@ Vagrant.configure(2) do |config|
     vb.customize ["modifyvm", :id, "--cpus", "1"]
     vb.customize ["modifyvm", :id, "--natdnshostresolver1", "on"]
     vb.customize ["modifyvm", :id, "--natdnsproxy1", "on"]
+
+    # If Virtualbox is version 5.0.0 or higher, enable the kvm paravirtualization
+    # provider for better performance.
+    begin
+      if VagrantPlugins::ProviderVirtualBox::Driver::Meta.new.version >= "5.0.0"
+        vb.customize ['modifyvm', :id, '--paravirtprovider', 'kvm']
+      end
+    rescue Vagrant::Errors::VirtualBoxNotDetected
+    end
   end
 
   # Synced Folders