Load Testing Blog
Setting Apache2 ulimit for Maximum Performance
As strange as it seems, when you start up the standard RedHat or CentOS release, it is not configured for running Apache2 with any sort of performance! In fact, even on a large server you’ll be lucky to handle 100 concurrent users on even simple web pages. So many websites have very few visitors so often its not noticeable, but even if you adjust all of the other apache2 settings, if you don’t bother to adjust the ulimits, the site will be handicapped by really bad performance.
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Load Testing with Virtual vs Real Browsers
Perhaps the most contentious issue in load testing today is whether to test with real or virtual browsers. Read through the issues and then leave a comment to let us know how you feel.
Which is More Real?
Load Tester PRO’s virtual browser recreates the HTTP data stream exactly as a real browser would, so from the server’s point of view it is identical to a real browser. For example, it automatically configures session tracking, cookies, and application state, just to name a few. The server is not aware that the HTML, images, and javascript it’s sending out are not actually … Continue reading »
Patch Available for IE SSL Bug
A recent Microsoft security advisory and subsequent patch unfortunately disabled SSL recording with Internet Explorer on all released versions of Web Performance Load Tester, Load Tester PRO, and Trainer. SSL recording with Firefox was not affect, but other browsers have not yet been tested.
If you have a current support contract you can update any 5.0 or later release by using Help->Software Updates, and selecting “Search for updates of currently installed features”. Follow the instructions to install patch 5.1.111161. If you have a current support contract, but have not yet upgraded to to 5.0 the most recent installer … Continue reading »
Handling Javascript and AJAX Callbacks
Overview
AJAX technologies present some special challenges for testing software – since it blurs the distinction between a traditional page-based web application and a rich client-server application. Most testing tools are specific to one or the other – and for very good reasons. This tutorial demonstrates one approach to handling AJAX callbacks in an AJAX-enabled web application using Web Performance Load Tester.
Prerequesites: This guide assumes a solid understanding of the Load Tester product. The Load Tester videos are a good introduction to the main features. It is assumed can record a testcase and exeute load tests using some of the … Continue reading »
Load Testing an Javascript or AJAX Application
Most of us are relieved that web applications are starting to behave more like desktop applications – i.e. smarter and easier to use. A little wow factor here and there doesn’t hurt either. Ease of use always has a cost, so it should come as no surprise that the AJAX applications are more difficult to develop. But you may be surprised that they can also be more difficult to load test.
The reason is fairly simple. Traditional web applications are relatively easy to model and simulate. The state of a user session, at any given time, is a combination of the … Continue reading »
Load Tester PRO™ 5.1 Released
Fast on the heels of the initial 5.0 PRO release, 5.1 is a major upgrade that includes support for mobile load testing, a completely resigned load test design and control system, improved support for dynamically scalable websites, Internet Explorer 10 support, and portal license manager integration.
Mobile Load Testing
The increasing web traffic from mobile devices has been noticed for years, but how much does it really affect a website? A recent study shows that 7% of web traffic is from mobile devices, which includes both phones and tablets. Because these devices use different browsers, and sometimes access different versions of a … Continue reading »
Spinout at the Carolina Motor Park
Nineteen cars started on Saturday, and Jason finished 3rd in a very boring race (after
the first lap he basically drove solo laps the whole time). So on
Sunday the top three finishers decided to skip qualifying entirely and
start at the back of the pack just to make things more exciting.
Unfortunately he got spun around while passing a slower car (at the 35second mark) on the
opening lap which put him dead last plus about a 20 second gap.
Fortunately he was able to make up some time and ended up seventh.
It was nearly sixth but for an out of class car got … Continue reading »
Going to the Velocity Conference in June? Save 20%
The Velocity Conference is the biggest and best web performance event in the field, and completely eclipses the testing conferences that add in performance as an afterthought. Well, if truth be told its the only conference entirely on the subject, but that’s besides the point. The others might have a separate performance track, while this entire conference is devoted to building, testing, and operating high volume sites.
http://velocityconf.com/velocity2012
We’re a media partner this year, so if you’re thinking of attending be sure to use this 20% discount code: WEBPER. The conference has … Continue reading »
2012 Racing Season Starts with a Crash
The 2012 car racing season got off to shaky start for our intrepid SpecE30 car and driver. The driver, Jason Tower, is still not back 100% after surgery to repair a torn ligament in his hand, but none-the-less headed to the Virginia International Raceway to try his luck at a weekend of SpecE30 racing.
The first race on Saturday was a disaster after a series of mishaps:
“… a car went off in turn 3 on the first lap which summoned the
emergency vehicles to the spot. The next time around another car
failed to see the yellow flag, … Continue reading »
Safari on New iPad 18% Faster than iPad 2
Thinking about getting the latest new iPad? One of the main activities for the iPad is web browsing, so we thought it would be fun to see how all three iPad models stacked up in the web page load time race.
Which Web Pages? These websites were picked for no particular reason other than we use them regularly and are likely representative of the browsing habits of a large number of our readers.
www.amazon.com
www.apple.com
www.facebook.com
www.microsoft.com
www.wikipedia.org
www.yahoo.com
Static vs. Real-World Testing
Typically browser performance is reported by running static benchmark tests that measure in a highly controlled way with few variables. Unfortunately, when you or I … Continue reading »