I recently read an article about how you can install HipHp Virtual Machine (HHVM) for a 2x+ speed boost on your site. The newest version of WordPress works 100% with HHVM, but unfortunately some of the plugins out there don’t. I decided the pros out weighed the cons and decided to install HHVM on my development server. Outlined below are the steps for installing it on your own.
wget -O - http://dl.hhvm.com/conf/hhvm.gpg.key | sudo apt-key add -
echo deb http://dl.hhvm.com/ubuntu saucy main | sudo tee /etc/apt/sources.list.d/hhvm.list
sudo apt-get update
sudo apt-get install hhvm
sudo update-rc.d hhvm defaults
sudo /etc/init.d/hhvm restart
sudo /usr/bin/update-alternatives --install /usr/bin/php php /usr/bin/hhvm 60
Now you want to edit the nginx vhost for the site you wish to enable HHVM on. Comment out the block of code that deals with .php files and then near the bottom of the vhost file add the following
Adding the include will include the HHVM config that was generated in the previous step. After you have done this you can then run a config test on nginx and if all passes issue a reload command.