These values govern how much time the server waits for a connection from the pool before it times out. In most cases, the default values work well. For detailed tuning information, see Tuning JDBC Connection Pools.
Some values that may affect performance are:
response-timeout-in-seconds -The time for which the load balancer plug-in will wait for a response before it declares an instance dead and fails over to the next instance in the cluster. Make this value large enough to accommodate the maximum latency for a request from the server instance under the worst (high load) conditions.
health checker: interval-in-seconds - Determines how frequently the load balancer pings the instance to see if it is healthy. Default value is 30 seconds. If the response-timeout-in-seconds is optimally tuned, and the server doesn’t have too much traffic, then the default value works well.
health checker: timeout-in-seconds - How long the load balancer waits after “pinging” an instance. The default value is 100 seconds.
The combination of the health checker’s interval-in-seconds and timeout-in-seconds values determine how much additional traffic goes from the load balancer plug-in to the server instances.
For more information on configuring the load balancer plug-in, see Configuring the HTTP Load Balancer in Sun GlassFish Enterprise Server 2.1 High Availability Administration Guide.
The sql_client time out value may affect performance.