By default, these components use an Apache Derby database that is included with DevTest. This database is adequate only for small deployments that do not require load and performance testing, and is not supported. For all other scenarios, configure DevTest to use an external database.
To ensure correct performance when using an external database, the database server and DevTest server should have high network bandwidth and low latency.
When run in a distributed configuration, DevTest depends on server components having a high-bandwidth, low-latency connection to a well-maintained, enterprise-class database.
All DevTest server components communicate directly with the database to record their actions. Any restriction to the flow of this data has adverse effects.
To ensure that your DevTest functions correctly, no DevTest server components should have a Round Trip Time (RTT) of greater than 20 ms to the database host. If the network latency exceeds this 20 ms value, you can expect performance problems.