2/3/2016 - bye hhvm

I've replaced hhvm with the more standard PHP-fpm, which should stop the site dying every hour or so.

What is hhvm? What is PHP-fpm? And how does this change stop the site from going down every hour?

pls, the site was down for like, 20 seconds at most.

a small explanation;

HHVM is a really fast PHP compiler, but is also really unstable.
PHP-FPM is the standard PHP compiler that's been around for years and is really stable.

The error that appeared on the site was due to me not remembering that Redis (a caching software we use) does not come packaged with PHP-FPM by default.

>20 seconds at most
>crashed every 25 seconds

yeah that would explain it
bye bye hhvm you will (not) be missed, whatever you are