This sounds like a pretty terrible topic, doesn’t it? Stress Testing. Sounds like it might be an interviewing method for new engineers.
Stress Testing is actually a great way to see if your servers can handle sudden jumps in traffic or sustained volumes of traffic (think of something going viral). I learned today that a small wordpress site I set up earlier could easily handle about 80 simultaneous active users before it’s response times started getting too high and it went into a downward spiral of responsiveness. I also learned that I could increase the number of CPUs and memory allocated to the virtual machine and it could handle significantly more simultaneous users. This tells me that if the company running the WordPress site wants to start up a viral campaign such that 10,000 people are going to be hitting the site within 10 minutes, I better make some significant investments in load balancing, additional hardware, and software necessary to make that happen. If however they don’t foresee any huge increases in traffic, then we can leave everything where it is and keep our costs down.
Do be careful running stress tests, and if at all possible, run them on dedicated hardware that will not affect production machines. Your stress test could very easily overwhelm the machine you’re testing and if you don’t have good control on aborting the test, you’ve basically taken yourself offline due to a self-induced overload attack.
Michael Berding August 20th, 2013
Posted In: Systems