Load Testing Blog
Load Testing Fallacies: It’s Not Ready for Testing
There is a new Load Testing 101 post over on the Dynatrace Blog. Overall, I think it is a pretty good article. However, it illustrates some of the fallacies of load testing that we hear from time to time. In this article, I want to dispel a fallacy that might be inadvertently reinforced by that post. Please note that I don’t want to speak for the authors – so I encourage you to read their article and judge their meaning for yourself.
Load Testing with IE 8.0, Firefox 3.5
The performance improvements in the latest browsers (Internet Explorer 8.0 and Firefox 3.5) have been eagerly awaited for many months…though they come at a price.
Removing Ad-servers and Click-trackers from your Load Test
We field a lot of questions about load testing websites with 3rd party components on the pages containing advertisements or user tracking mechanisms. For many of our users, we recommend leaving these out of the load test entirely. For some users this causes some concern over maintaining the realism of the load test. In this post, I’m going to discuss the advantages and disadvantages of dealing with these in a load test – and then provide some quick instructions for easily keeping these services out of your load test.
I’ll start by looking at the possible advantages of including these services … Continue reading »
Velocity Conference – Day 3
A great deal of time at the Velocity Conference has been spent on client-side performance optimization. This encompasses changes to the page structure and sub-elements to speed the delivery of a usable page to the user. Here at Web Performance, we have primarily been concerned with server-side performance – due to our focus on load-testing. Client-side optimization, however, benefits the users even when the server is not under load. It is something that we would like to expend more effort on when working with our clients.
Some of the most common client-side optimization techniques discussed were:
1) Reducing round-trips to the server
reduce … Continue reading »
Business Impacts of Performance
One of the opening sessions of the Velocity 2009 conference was a joint session with engineers from Microsoft Live Search (Bing) and Google Search…yes, they were together on the same stage :>
Both organizations wanted to measure the effects of performance on the business – i.e. on revenue. Revenue for search sites is based on the number of searches and on the number of clicks on results. Both of the search giants have experimentation platforms which allow them to send a small portion of real users to a different version of the search platform, where they can modify the user experience … Continue reading »
Velocity Conference – Day 1
My first day at Velocity was long, but fun. I breathed a sigh of relief when my luggage finally arrived…10 hours after I did.
I attended part of a Load Testing workshop early in the afternoon that raised some interesting topics:
Why are steady ramps bad? They showed some examples of how this approach can result in the wrong conclusions about system capacity. I agreed heartily – I’ve blogged on the merits of a stepped ramp in load tests previously.
Abandonment rates – This is a feature that I’d like to get into Load Tester sooner rather than later. A basic … Continue reading »
Performance Goals and Analysis Methods
We are getting close enough to the 3.6 release that I’m able to talk more about the new features – so look for more posts in the next few days. I blogged previously about the improved performance goal features, but at the time, I could not detail how they would be used to improve Load Tester’s analysis reports.
Search view added for Load Tester 3.6
As web applications become more sophisticated, configuration of testcases used to test the application becomes more difficult. The need for customization, beyond the automatic configuration provided in Load Tester, means that testers need to spend more time understanding the application. One common scenario finds the tester searching through the application pages to determine where a field is assigned, in order to configure a custom extractor to get the value dynamically. Several of the features added in Load Tester 3.6 makes this process much easier.
In the example below, the Search View is used to find a field with dropUsers in the … Continue reading »
Sharepoint Performance Case Study
Is your Sharepoint website slow? Are the servers under-utilized and the database shows no locking, but response times for the pages are still poor? Is Sharepoint unstable under load? We recently helped a client through the grueling process of optimizing and stabilizing a large Sharepoint installation. Once we discovered the underlying causes, the fixes were rather easy, but finding the performance bottlenecks was time consuming. We’ve described the process and the findings, so you can skip the hard part!
Read the case study.
Virtual User Calculators
Customers frequently ask us for help deciding how many virtual users they need for their load tests. We have a number of formulas for calculating this, depending on what information the customer has available. Last weekend I built online calculators for a few of the more popular variations. Give them a try!
If these don’t apply to the data you have available, contact us and we’ll be happy to help you calculate the number of simulated users required for your specific needs!