HHVM/About

HHVM (also known as the HipHop Virtual Machine) is a virtual machine for PHP, with an associated just-in-time (JIT) compiler. Deploying HHVM on a MediaWiki wiki should lead to performance improvements across the board for most users.

Currently, on Wikimedia wikis, you can opt-in to using HHVM through the beta features tab in your preferences. You can verify the feature was enabled properly by visiting Special:Version on your wiki, and checking that it says "HHVM". Once the developers and sysadmins are satisfied that it is stable enough, it will become the default for all users.

Our preliminary benchmarks show that HHVM is significantly faster than the current PHP interpreter.

FAQ

 * How do I know if an edit was made via HHVM?
 * All edits and log entries made via HHVM are tagged so they can be filtered on Special:RecentChanges.
 * Why are edits made using gadgets not using HHVM?
 * Most gadgets use the API to edit, which currently does not support this beta feature.
 * What are the known issues with HHVM?
 * All bugs related to HHVM are tagged with the keyword "hhvm" on Bugzilla, so you can use a saved search to see all open bugs.