I've had the opertunity to try a variety of different server configurations but never really got around to trying HHVM with Magento until recently. I thought I would share a detailed walkthrough of configuring a single instance Magento server running Nginx + Fast CGI + HHVM / PHP-FPM + Redis + Percona. For the purpose of this blog post I'm assuming you are using Fedora, CentOS, or in my case RHEL 6.5.
Please note: I'm 100% open to suggestions. If you see something I did that needs to be done a different way, please let me know. I haven't included my Perconca my.conf file yet. I will shortly. Also I plan on trying this same test with HHVM 3.3 and PHP 7.
Install the EPEL, Webtatic, and REMI repos
rpm -Uvh http://download.fedoraproject.org/pub/epel/6/i386/epel-release-6-8.noarch.rpm rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-6.rpm rpm -Uvh http://mirror.webtatic.com/yum/el6/latest.rpm