This parameter specifies the number of seconds that an application will wait to obtain a lock, helping avoid global deadlocks for applications.
If you set this parameter to 0, locks are not waited for. In this situation, if no lock is available at the time of the request, the application immediately receives a -911.
Recommendation: In a transaction processing (OLTP) environment, you can use an initial starting value of 30 seconds. In a query-only environment you could start with a higher value. In both cases, you should use benchmarking techniques to tune this parameter.
The value should be set to quickly detect waits that are occurring because of an abnormal situation, such as a transaction that is stalled (possibly as a result of a user leaving their workstation). You should set it high enough so valid lock requests do not time out because of peak workloads, during which time, there is more waiting for locks.
You can use the database system monitor to help you track the number of times an application (connection) experienced a lock timeout or that a database detected a timeout situation for all applications that were connected.