Now that you have an estimate of the number of CPUs for your portal deployment, use a trial deployment to measure the performance of the portal. Use load balancing and stress tests to determine:
Throughput, the amount of data processed in a specified amount of time
Latency, the period of time that one component is waiting for another component
Maximum number of concurrent sessions
Portal samples are provided with the Portal Server. You can use them, with channels similar to the ones you will use, to create a load on the system. The samples are located on the Portal Desktop.
Use a trial deployment to determine your final sizing estimates. A trial deployment helps you to size back-end integration to avoid potential bottlenecks with Portal Server operations.