The LANSA stack templates create a scalable web server and application server environment. This environment is scaled based on the CPU utilization of each server. The defaults provided may need to be adjusted to match the performance profile of your application. Its highly recommended to use a load testing tool to run a typical load that you expect your application to experience. Such tools may simulate hundreds of users concurrently accessing your application. The knowledge you gain from running the tests will be invaluable in assessing the configuration options required for production.
A very important decision to be made is what size of database virtual machine you will require. It is an easy task to scale a database instance up and down, but it's a manual task which requires the whole stack to be taken offline whilst it occurs. Each virtual machine size has an upper limit on the number of concurrent users it may practically support. LANSA sets the upper limit as an average response time of under 2 seconds. This is the response time as seen by the user in their browser. For indicative configurations that you may use as a starting point for determining the appropriate database virtual machine, refer to LANSA WAM Performance and Pricing Guidelines in CTE015 – Subscribe to the LANSA Image.