I thought it would be fun to see how Wikipedia defines some of the key terms we deal with in web application development and testing.

What is the Slashdot Effect?

The Slashdot effect occurs when a smaller website is flooded with visitors, usually as a result of being linked to from a high profile website. The name comes from the Linux and Open Source blog http://slashdot.org, a site which handles 80 million page views a month. Many home servers or low bandwidth sites that post content interesting to one of these larger blogs have experienced significant downtime when the traffic from Slashdot suddenly migrates to their own servers. Performance engineering for the Slashdot effect is essentially engineering for a worst case scenario - but that worst-case involves more traffic than developers could ever have imagined!

Many CIOs do not embrace cloud computing. They have pressures from stakeholders to make system service levels "five nines", and clouds don't offer those SLAs. The trade-off is between highly redundant and available systems at a high cost to maintain compared to much lower cost without the guarantee of high availability. Cloud server platforms are relatively very inexpensive, but it isn't perfect.

On October 14, 1962, six thousand (yes 6,000) Unification church couples got married in Korea. Think about it...that is probably the largest STRESS test of all time! :-)

Before we get to the software testing news, here are some other events that happened on this day in history that I find interesting:

• Space probe Magellan burns up in atmosphere of Venus in 1994
  

A Little Cache Goes a Long Way

Drupal is the target of load testing for this series of articles. If this is your first time reading any of the articles in this series, please review the introduction and summary called Load Testing Drupal for a good context of what we are doing.

Some of the benefits of load testing are:

• Reduce risk of downtime
• Improve deployment quality
• Find performance bottlenecks
• Increase customer satisfaction
• Provide tangible statistics to developers
• Create system benchmarks useful throughout SDLC
• Improve scalability of your app
• Minimize risk related to performance requirements
• Reduce costs of failure
• Maximize marketing campaign funds
• Optimize hardware and software costs through accurate capacity metrics
• Reduce risk associated with SLAs
  

Bob Williams, Senior Manager e-Commerce Marketing at Harland Clarke, has a nice post about performance testing, load testing, and stress testing. He titles it Customer focused eCommerce: Volume testing techniques

Load tests identify performance problems that will affect users. If the web app takes 15 seconds to respond when someone is putting a widget into your e-commerce shopping cart, the probability of that user inputting a credit card number decreases dramatically. Cognitive psychologists have show distinct correlation between user confidence and unexpected application behavior. When the system does something "odd", then people don't trust it. Slow is bad. Slow response loses visitors and loses revenue. It can cost your company $ millions (NO EXAGGERATION)!

Basilio Briceno is the Senior Developer at Naranya - one of the leading new media companies in LatinAmerica, with special focus in the mobile entertainment and mobile marketing world. He is also a Community Member of the Mozilla Foundation and Project Lead at Tlalokes PHP framework.

Basilio is or has been a college professor, a public speaker, and an independent consultant with these specialties: PHP, UNIX, GNU/Linux, FreeBSD, Solaris, Apache, IIS, Bind, Bash, Photoshop, Gimp, (X)HTML, DB/2, Websphere, JSP, JSF, Javascript, MySQL, Oracle, Perl, PostgreSQL, Postfix, and XML. Check out his personal blog site when you get a chance.

Let's start the interview.

How much involvement do you have with load and performance testing?

That's what I do everyday, and that's why companies hire me. My principal task is to be the most worried person in the company about performance testing. That's why I try to be involved in every aspect, from UI testing, to load testing, and OS tuning.