Support

Hello,

thank you very much for the report, there was indeed a bug in the session purge feature, it was running only for backend user.

Please download the latest dev release and try again, it should fix your issue.

Session cleaner is a "lazy" plugin: it fires only if enough time has passed and a visitor hits your site, so its timing is not very accurate.

However you should not worry about your using being logged out: we do not simply truncate the table, but we ask Joomla to perform garbage collection. This means that Joomla will remove all records from the table that refer to expired sessions, people that will have to authenticate anyway, but we delete the record to save space and keep the session table in good shape.

Session optimizer
It will run the command OPTIMIZE TABLE #__sessions on the database. This is useful only if you have your database engine set to MyISAM, otherwise it won't do much

Session cleaner
This will clear the session table from people whom session has already expired. Please note that right now table cleaning is performed randomly each time a visitor hits your page to avoid stressing the database too much (if I remember correctly there's a 1 in 5 chance to do such cleaning).
Running a cleaner will delete those logged out records on fixed intervals.

Please remember that Joomla will always create a session record even for guest users. If you have database issues caused by session table, I'd suggest you to do some research about switching the session table type to MEMORY or to use a different session provider such as Redis.