Load Testing Blog
Configuring File Uploads
When a testcase has a file upload in it, Load Tester automatically handles the file upload during replays and load tests. However, in many tests each user should upload different file contents (and possibly use a different file name). Load Tester has streamlined this process to make it very easy to handle. Just follow these easy steps:
1) Gather the set of files to be uploaded
2) Import them into Load Tester (Window > Preferences > Web Performance > File Upload) and generate a dataset
3) Find the file field in the testcase using the Fields View
4) Configure the field to use the … 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 enabled, just run your Load Test as normal. When examining the … 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 out:
1. Run a replay with your existing testcases. If the replay fails … Continue reading »
Introduction to Load Testing: Part One
The website is completed or mostly completed and you have been advised to do a load test, but you are not quite sure were to begin. First things first, a basic understanding of load testing procedure is needed. The load testing procedure mostly involves understanding the web-application that will be tested. Understanding the applications refers to many different factors such as:
Understanding the functionality of the website.
Understanding the general network layout.
Understanding the software and hardware used by the system.
These factors are useful for a number of reasons, not only do they make the load testing process easier, but they can help … Continue reading »
Load Testing Back to Basics: TCP Connection Failures
Load Tester is a web site load testing tool, and as such we deal primarily with the most popular Internet communications protocol: the Hypertext Transfer Protocol, or HTTP, which controls the request and transmission of web pages between browser clients and web servers. HTTP is based on a lower-level protocol known as the Transmission Control Protocol, or TCP. For the most part, TCP works in the background, but its proper function is critical to your website, and problems at the TCP level can show up in many different ways during a load test. … 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 / or it may share the same SSL certificates which identify it with the hostname … 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 intended mainly for replays and small tests, so in this … Continue reading »
How User Ramping Works – Part Two
In part 1 of How User Ramping Works, we discussed how to set up a user ramp configuration for a test. When you’ve done that, recorded and replayed your test cases to perfection, loaded your datasets, configured your load engines, and set up your server agents, what actually happens when you push the big green button?
The first thing Load Tester does is go through a setup sequence that configures the load engines for the coming test. This can take a while, especially if you’ve configured large datasets or large numbers of files to be … Continue reading »
Status code 200 didn’t match expected: 304
Suppose you’ve got a testcase that either worked in the past, or just works sometimes, but now seems to be giving you an error: “The status code of the response (200) did not match the status code of the response in the Testcase (304)”. This particular error message is probably not a serious error, but it usually means that your test isn’t quite emulating what a real browser would do.
Fixing this problem in Load Tester is usually easy. Just right click on your testcase, select Properties, and then go to the “Restart Options” tab. Simply check the last checkbox: “Update … Continue reading »
Configuring and Analyzing Performance Goals
A tutorial on customizing the analysis that Load Tester automatically provides in its reports.
