Load Testing tips for Database Administrators
Nearly every useful web application is backed by some sort of database – usually a relational database. Many database administrators (DBAs) have never participated in a load-testing campaign and are sometimes even considered tangential to the load testing process.
However, your DBA is a crucial part of the load-testing team. In addition to the obvious skills of database performance analysis and tuning, the DBA brings other advantages to the project:
- insight into how the application interacts with the database that may not be obvious from the perspective of other team members
- ability to quickly backup and restore various database snapshots to increase consistency in the testing effort
There is one disadvantage: If your DBA is involved in the testing, it is a lot harder to blame them when things go wrong! (and we never pass on a chance to give our DBAs a hard time 
)
This quote from Why IBM DB2 DBAs Love Load Testing illustrates one reason we love working with customers who get their DBAs involved with the load testing process:
“DBAs prefer to be proactive and deal with potential issues before they become production nightmares.”
What should a DBA be looking for during a load test? Here are the key issues to be watching for:
- deadlocks
- timeouts
- hot spots
- sub-optimal object definitions
- sub-optimal index and SQL
- unexpected table growth
The article I referenced above has a DB2-specific title, but actually applies equally well to most web-based systems. I recommend passing it on to your DBAs when you invite them to your next load testing project.
Chris Merrill, Chief Engineer
When his dad brought home a Commodore PET computer, Chris was drawn into computers. 7 years later, after finishing his degree in Computer and Electrical Engineering at Purdue University, he found himself writing software for industrial control systems. His first foray into testing software resulted in an innovative control system for testing lubricants in automotive engines. The Internet grabbed his attention and he became one of the first Sun Certified Java Developers. His focus then locked on performance testing of websites. As Chief Engineer for Web Performance since 2001, Chris now spends his time turning real-world testing challenges into new features for the Load Tester product.