Want to find out if an engineer performance tested their application? Tell them to do one thing for you: Make it crash. That’s right, bring the network traffic to a crawl; force it to run out of memory; take away disk space. Have them demonstrate that they know the limits of their application so well, they can make it fall over at will. If they’re bad ass, they’ll whip out a test script and start it up. In a few minutes, the application should crash in a predictable way — predictable if the application is well designed. But really, my point here is to try to make it crash but not be able to.