Tuning the application server

Use these starting values for application server tuning parameters to tune your application servers. The parameters are key to the performance of Cúram on applications servers such as WebSphere® Application Server (WAS) and WebLogic Server (WLS). Refine the values during load testing of the system and during monitoring of production. A load test phase in the project is highly recommended.

Determine the number of application servers in your application clusters that are based on availability requirements. An initial starting point is to have at least two application servers per cluster. However, it is recommended to use three or more application servers per cluster to ensure good performance and quality of service in case of server failure.

Another consideration for the number of application servers is the number of cores that are available from the operating system. In general, it is recommended to keep the number of threads in a Cúram application server to a low multiplier of the number of cores, as described in the Thread pools section. However, a high number of cores can result in a very high number of threads and, therefore, a higher probability of threads contending on Java locks. In that case, it is advisable to split the threads across multiple application servers instead of just one, which reduces the probability of contention. However, a drawback of this approach is increased memory utilization on the operating system as multiple JVMs are needed.