Following the upgrade to XenForo 1.4 today, database performance was noticeably degraded. I'm seeing entries in the mysql slow query log every few minutes like the following: Code: # Query_time: 19.433014 Lock_time: 0.000054 Rows_sent: 7 Rows_examined: 14136216 SET timestamp=1410276290; SELECT message.*, user.*, IF(user.username IS NULL, message.username, user.username) AS username, user_profile.* , session_activity.view_date AS last_view_date FROM xf_conversation_message AS message LEFT JOIN xf_user AS user ON (user.user_id = message.user_id) LEFT JOIN xf_user_profile AS user_profile ON (user_profile.user_id = message.user_id) LEFT JOIN xf_session_activity AS session_activity ON (message.user_id > 0 AND session_activity.user_id = message.user_id) WHERE message.conversation_id = '125327' ORDER BY message.message_date LIMIT 40 OFFSET 3520; I see that xf_session_activity is now joined in this query to enable showing the User Online Status Indicator. Disabling the showMessageOnlineStatus option resolves the performance issue. Have other large XF installations encountered this issue? My site is http://www.redcafe.net/ It's a nice feature and I'd like to keep it enabled but if it's not suitable for larger forums then so be it.