Recently I wanted to convert all my link shorteners to YOURLS which is a pretty awesome, easy to use link shortener. I could have easily setup YOURLS 8 times, but that felt unnecessary since all the files are static and all the data is stored in MySQL. So I modified the config to allow for multiple databases based on the domain it is being accessed from.
PHP 7 was officially released on Dec 3, 2015. After reading about the speed benefits for WordPress and other web applications, I decided to give it a try and upgrade. I have one WP site that was particularly slow. At some times could take 20 seconds to load. After transferring to PHP 7 server I was getting load time 8-4 seconds.