St. Louis CMGBirds of a Feather Session May 2008

“How to Marry Performance Testing Information with Capacity

Planning Predictions”

What is a “Birds of a Feather” Session?

• An opportunity for individuals from related fields to share ideas and experience in a particular problem space

• Discussion, not a presentation

Today’s Problem

• You are a Capacity Planner for Widget Corp.

• Widget Corp recently purchased Gadget Inc., a smaller competitor.

• Sales associates at Gadget are being migrated to Widget’s Sales application

• You are tasked with ensuring Capacity for the combined roll out.

The Facts

• Business Analysts have determined that Gadget will add roughly 30% in new sales volume.

• Your performance testers developed a load model based on a 30% transaction increase, but have raised a red flag – based on the total number of Gadget Sales associates, a 30% transaction increase means associates are closing a sale every 7 minutes, which is known to be untrue.

First Question

• Management has expressed concerns that the load model is incorrect. What is wrong with the load model, and how do we confirm that we have a correct understanding of our future state?

Complications

• Load model is now assumed to be correct. However, the test environment available for running performance tests does not look much like production. It is clear that the full production load will not run in this environment. What techniques can we use to alter the load model proportionately so that utilization can be accurately predicted?

Example Environment Comparison

Production• 4 4 CPU application

servers• 12 CPU Oracle DB• SAN storage (db size

1 TB)

Test• 2 2 CPU application

servers• 6 CPU Oracle DB• SAN storage (db size

100 GB)