For multiple reasons we have held back on upgrading our dumps infrastructure from Ubuntu Trusty to a newer distribution. Also, because of some HHVM bugs, we never switched to use HHVM for dumps and we're still producing those with PHP 5.5.
Since we now want to drop PHP 5.x support from MediaWiki 1.31, we need to either upgrade the dump hosts to a newer distribution with a recent version of HHVM (which will be able to run dumps) or to one using PHP 7.0. So our options will be:
- Upgrade to debian jessie and run dumps with HHVM
- Upgrade to debian stretch and run dumps with PHP 7.0
This task is a blocker to the actual implementation of the RfC, and should track progress on this.