Chapter 2. Performance Tuning and Stress Testing Reviewed

With millions of dollars and thousands of hours invested, the last thing you want after a major SAP implementation, upgrade, IT consolidation, or change control wave is a surprise on the big day of Go-Live or a cutover to a new or updated system. Yet, that is exactly what occurs time and time again in the real world. Why? Because even though a huge, carefully managed budget may have been set aside and painstakingly adhered to, many companies implementing, upgrading, or simply maintaining SAP AG's R/3 or a mySAP Business Suite component simply do not understand the value of or cost in performing a holistic stress test of both their critical enterprise business applications and the technology underpinning these applications. More often than not, a company focuses solely on functional testing—ensuring that the business can get its day-in and day-out job done using the new system to conduct company operations or business transactions—at the expense of stress or “load” testing. Because of this situation, instead of Go-Live representing a best-case nonevent, it more closely resembles a roll of the dice. And, chances are good that most companies will not hit the jackpot; indeed, the road of many SAP implementations and upgrades post Go-Live is littered with poor code, misconfigured hardware, and less than optimally tuned databases. In these cases, although it's true that the system can functionally perform what it was intended to do (e.g., create and track sales orders or facilitate inventory management), it does so either slower than is possible, or in a manner that hinders much of the value originally envisioned in deploying the new application—to the point of hurting the business's ability to service its end users and other customers in a timely manner. In the end, the business is forced to limp along for a period of time until the performance and tuning issues are finally worked out over time, if at all.

Fortunately, the great majority of performance-related unknowns surrounding Go-Live may be identified and mitigated, if not completely eliminated, before cutover, by giving proper attention to stress testing and follow-on performance tuning. This book's primary goal, therefore, is to help you understand exactly how stress testing and real-world performance tuning fit within the big picture of an SAP system's lifecycle. In the next several hundred pages, I will walk you through pretuning your entire SAP Technology Stack, planning for and executing an end-to-end application-layer SAP stress test, and leveraging your newfound knowledge to optimize your SAP system before a single one of your system's end users is ever asked to log on to your new or updated system. In doing so, I will address not only the critical nature of working with the business to identify success criteria and approaches useful in staffing your SAP “testing and tuning” project team but also the detailed steps necessary to successfully navigate through a maze of technology and business-process decisions. Of course, serious attention to your unique mySAP applications, timelines, budgets, and performance goals is provided along the way, too. And, to keep all of us grounded in the real world, I have shared in many of these chapters my own customer stories, findings, anecdotes, and lessons learned, along with best practices and approaches as identified by me, SAP AG, or SAP's many technology partners.