A database error has occurred. Did you forget to run maintenance/update.php after upgrading? See: https://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script
Query: SELECT value,exptime FROM `mw_objectcache` WHERE keyname = 'tpot_2-mw_:stats:request_without_session' LIMIT 1 FOR UPDATE
Function: SqlBagOStuff::incr
Error: 1213 Deadlock found when trying to get lock; try restarting transaction (localhost)