Autoslave keeps track of which tables have been written to, and forces read from the master afterwards within a given time interval (assumed maximum replication lag: default 2 seconds).
A table (autoslave_affected_tables) is used for keeping track of these tables which have been written to.
To control the assumed replication lag time, configure it in settings.php
<?php
$databases['default']['default'] = array (
'driver'=> 'autoslave',
'master'=> array('master'),
'slave'=> array('slave'),
'replication lag'=> 5, // Stay on master for affected tables for 5 seconds
'global replication lag'=> TRUE, // Stay on master for concurrent requests. Defaults to TRUE
);
?>The "global replication lag" controls whether or not these affected tables should be used by all users. If set to FALSE, the autoslave_affected_tables will not be used, but session storage will be used instead for the user who affected the tables. Disabling "global replication lag" is not advised, as concurrent requests may then pollute cache with old data.