When this option is set to On, the database server logs information about deadlocks in an internal buffer. The size of the
buffer is fixed at 10000 bytes. You can view the deadlock information using the sa_report_deadlocks stored procedure. The
contents of the buffer are retained when this option is set to Off.
When deadlock occurs, information is reported for only those connections involved in the deadlock. The order in which connections
are reported is based on which connection is waiting for which row. For thread deadlocks, information is reported about all
connections.
When you have deadlock reporting turned on, you can also use the Deadlock system event to take action when a deadlock occurs.
See System events.
You can also change the setting of this option by using the DeadlockLogging property with the sa_server_option system procedure.