Is it possible to run CiviCRM on HHVM
I have tested this and have duplicated the WSOD error.  The error I get in the hhvm log is Fatal error: Cannot access private property Civi\\Core\\Transaction\\Frame::$state  As I am not that familar with HHVM I cannot take it much further.

Jeremy, do you get the same issue with Drupal and CiviCRM?

I have been satisfied with PHP-FPM performance, so while I hate to give things up, that may be the quickest path to getting this to work.