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.
As I sit here on this Monday morning and try to figure out what I should do first, it hits me that today is the beginning of an exciting year. 2009 will probably be remembered by most people as the big global economic recession. For me, 2009 will be significant because of the launch of LoadStorm.
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!
Ricardo Sueiras is a self-professed “IT professional and geek” (found that on his blog. His formal title is J2EE Systems Architect at PricewaterhouseCoopers LLP in Canterbury, United Kingdom.
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.
The following is an interview with David Makogon, and he shares his thoughts with us on load testing.
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
I told this to an “expert” at the Association of Software Testing conference this year. He response was something like, “Are you kidding me?!! You’d have to be stupid to load test your production setup.”
What occurred to me later in the conversation was that this guy works for a Fortune 100 company and has a six-figure annual budget (not counting his salary) just for performance engineering.
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.
We all know how critical load testing is to a successful development effort … underestimate the possible success of your site, and you may have sabotaged that very success! If you are looking into simulated virtual user load testing for the thorough, comprehensive analysis it can offer developers, here we have some tips and tricks to make the process easier and faster.
Recognize that some questions cannot be answered
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
My thanks to Lawrence Nuanez for sharing his insights and testing expertise with us. In this email interview, Lawrence talks about his views on software testing, load testing, test automation, and off-shoring.
As a Senior Consultant for ProtoTest, Lawrence’s focus is mainly on load and performance testing, and he has several years of experience helping both SME and Fortune 500 clients by designing custom test plans. Use of both proprietary and open-source tools is always considered to ensure that best fit for the customer.
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
Dr. J Singh is a principal of Quantitecture where he helps clients improve the success rate of large software development projects. Dr. Singh has been associated with system performance for 20+ years, and was the Director of Software Development at Fidelity Investments. He managed a system performance group and created several successful new products.
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)!
Mr. Prickett, my 12th grade English teacher, was one of my all-time favorites. One day while I was arguing with him about why he took off points on my paper, this popped out of my mouth: “I assumed you knew the character because it was part of the assignment!”
He proceeded to walk to the chalk board (I’m old, before whiteboards), and he wrote “A S S U M E” in huge letters. Now he had everyone’s full attention. As he explained, he circled the letters for emphasis, “for U to assume is to make an A S S out of both U and M E!
I’ve forgotten most of what he taught us, but I’ll never forget that lesson. So I decided to not assume that people coming to our sight will know much about load testing. Hence, this post. I hope you find it useful because it isn’t intended to talk down to anyone.
There is too much to say about load testing in just one blog post, so I will break this down into the key questions: what, why, who, when, how, and where. Let’s start with “what”.
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.