This morning (US EDT) we migrated our database over to Amazon RDS and hopefully you did not experience any downtime. Everything seems to be running smoothly now, and this change allows us to store more historical data, so there should not be any more purging of records for the graphs from this point forward. We may have to purge older data if the performance of the database decreases, but we will address that issue as it occurs.
Thanks!
-Z
