Business Case Reasons for Load Testing
Typically web load test efforts happen immediately before deployment or shortly after deployment, when live usage has determined that performance is inadequate. Performing the load testing at this stage in the project is much more costly than it would have been earlier in the development cycle.
Load testing, even at a minimal level, throughout the development cycle will pay for itself by the time the project is complete.
Business Benefits of Load Testing
- Lower IT infrastructure costs through tuning and accurate capacity planning before deployment (serves to get more out of existing investments)
- Mitigation of Risk that customers will find site performance unsatisfactory and go elsewhere (serves to increase online sales by imporving customer satisfaction and loyalty)
- Establish and monitor performance, reliability and availability of web sites to satisfy Service Level Agreements with partners, customers and investors.
- Accurately assess and report application performance characteristics before deployment
- Uncover the root cause of performance problems quickly and easily
- Find ways to improve operational efficiency by processing more transactions in less time
Essential Business Questions about Load
- Will critical applications fail if they are pushed hard with x number of simultaneous users?
- Will heavily used applications represent an unmanageable load on system resources?
- Will demands caused by seasonal peaks exceed the capacity of existing software systems?
- Will software limitations impede the organization's ability to merge or acquire new business units? To that end, if computing capacity is increased, will the new application scale well?
- If hardware upgrades are being considered, will new processor capacity meet anticipated demand?
- What will happen at the application failover point? Will fault tolerant measures ensure service continuation?
Reasons for Needing Load Testing Solutions
- Diagnose existing performance issues
- Identify performance bottlenecks prior to deployment
- Ensure site will support required load
- Determine maximum user load a site will support
- Capacity planning of website infrastructure
- Benchmark various system configurations
- Required for Development process as part of best solutions assessment
- Required for Quality Assurance process to establish satisfaction of requirements
Multiple Users
When a web application exposes complex information structures and implements complex business logic, synchronization problems resulting from simultaneous users accessing and modifying the same data can cause system defects that cannot be detected with single-user mode functional testing tools.
These types of defects frequently result in incorrect behavior and/or data corruption - sometimes even complete application lockup or crashing. They are also the hardest to detect and reproduce - and are frequently blamed on other sources, such as the users, when they cannot be easily reproduced by the developers or testers.