Load Testing Blog
Showing posts tagged “Load Tester”
Fixing: Unable to Establish Connection to the server
In this example case, we ran into a situation where a load engine could not resolve the hostname of the server being tested, even though Load Tester was able to record & replay against the server without any difficulty. This problem appears immediately, but only when running a Load Test with the troubled load engine. By using the Engines View in Load Tester, we were able to select and use each Load Engine separately in a Load Test, until the faulty engine had been isolated (this sort of … Continue reading »
Knowing your Security with Stress Testing
In the past, we’ve had plenty of discussion on how performance effects user experience, and how that relates to conversions. But, can a server’s performance effect it’s security?
During a previous test, we had a customer whose site included a contact form. The user would complete the contact form in their browser, and the application server would convert this response into an e-mail and send it through a mail server. The contact form, coupled with the use of a CAPTCHA, helps to cut back on undesirable messages. During our testing, we … Continue reading »
Testing tip: Make it Fail
We recently had a case of debugging a testcase where Load Tester reported an error with a page that looked and appeared just as it should, except it was missing a link the user needed to move forward. Debugging this case was easy: examine the replay two pages prior to the error, and the server had added a red error message to the page indicating the selected criteria was not valid.
So why didn’t Load Tester flag this error from the server? Beneath the error message, the page was exactly identical to … Continue reading »
Tips for Successfully Testing from the Cloud
With Load Tester 4, we’ve made it easy to harness Amazon’s power for Load Engines quickly and inexpensively. Once you’ve familiarized yourself with the basics, here are a few rules of thumb:
1. Get to know the Amazon EC2 Console . The console will quickly tell you what instances you have running – and subsequently what you are getting billed for.
Note that the console shows you only data for a selected region, so you should check each region separately. Load Tester will automatically prompt you after a test … Continue reading »
Load Testing Metrics: Comparing to the Median
Once you’ve been using Load Tester for a while, it’s easy to find the minimum, maximum, and average page durations. But how does that compare against the median page duration, or percentiles?
Starting with Load Tester 3.6, these measurements can now be made, but it’s been made easier to find in Load Tester 4.1. First, you will need to enable “Detailed Page Durations”. In Load Tester 4.1, simply make sure the “Detailed Page Durations” option is checked on the “Data Collection” section of the Load Test Configuration editor.
With that setting … Continue reading »
Keeping Your Load Testing Cases Current (How To)
Maybe you’ve just finished your first crack at testing, handed some results up to the development team, and are just got a note that the dev team has revamped the site in preparation for the next test. Or maybe you completed testing last month and are ready to retest the site against any regressions. Are all the testcases setup from the last round of testing still going to work? Are you going to have to create all new testcases? Here are a few quick ways to find … Continue reading »
Simulated DNS Load Balancing Improves Testing Accuracy
With the release of Load Tester 4.1, we’ve been discussing some of the new features available in this release. One of those features is Simulated DNS Load Balancing. This feature offers improved testing accuracy over previous versions of Load Tester.
This feature is designed for systems which may use DNS to alias a single hostname to many different IP addresses, allowing the DNS system to provide load balancing. This works effectively when the users or load engines greatly outnumber the number of servers, and are well distributed and not in … Continue reading »
Keeping your HOSTS files in sync with Load Tester 4.1
Load Tester 4.1 has a number of exciting new features, but in this post, let’s discuss one of the less obvious features: a hosts file which is automatically synchronized with all your Load Engines.
Consider how often this happens: the development environment is mirrored from your production environment, and then updated to an internal version of the application, ready for testing. Since the development environment is otherwise a mirror of the production system, it is configured with the same virtual hostnames as your production environment, and / … Continue reading »
Load Engine Tuning: JVM Memory Optimization
The Web Performance load engine is the software Load Tester uses to create virtual users and generate load on the target. As with Load Tester, the load engine is a Java-based application that runs on its own Java virtual machine, which is included in the installation. There are two places the load engine is used: the local engine, which is included with Load Tester and runs inside the Load Tester JVM; and the remote engine, which is a standalone installation with its own JVM. The local engine is limited and … Continue reading »
For Bell Canada, Early Performance Testing Spells Success
When Bell Canada began development of an important new customer-facing application, project lead Mr. Roger Bejjani knew he needed to find a web testing tool that would help fine-tune performance throughout the development process and into production. Having used Empirix (purchased by Oracle) and Load Runner (purchased by HP)in the past, he decided to forgo overpriced software and look for a tool that would give him the functionality he needed at a more reasonable price. The main requirement would be load testing HTTP and HTTPS requests, and the … Continue reading »
