Auth User update time on mysql

Hello i am keeping session information in mysql only.. What i notice is, when a user logs in, only after a few mins i see the sql tables are updated about this user. So, if i check max-session number via sql too, user can log in a few times because, the user can not be found as online on sql side... Is there a wait limit on sql update? If so, is there a way to lower this timing?