Load Testing Blog
Showing posts tagged “Load Tester”
Load Testing Fallacies: The Test Scenarios Must Be Completely Accurate
Last time, I talked about why it is ok to start testing early in the development process. I’m going to continue that thought process to discuss load testing without complete performance requirements. This Load Testing 101 article says “If the real end user is going to do work with your application in a totally different way than you test you are as good as with no testing at all.” While there is a nugget of truth hidden in there, it is easy to take away the wrong understanding.
One interpretation of that statement would be that “you must have … Continue reading »
Why is my Page being Hit more than Once per View?
During testing of some sites, we found an strange case where pages seem to download themselves. What does this look like?
Note that the page gets requested, and seems to request itself while it is rendering. This has an obvious problem: the dynamic content is being requested twice as many times as necessary, causing the server to have to render it twice as often as necessary. If users turn off Load Tester’s “streaming” feature while recording, this looks a little different: the 2nd instance of the request is still made, but instead we get an error message: “Connection to server abandoned … Continue reading »
How User Ramping Works – Part One
How we add new virtual users to a test can be confusing when you’re first starting out with Load Tester, and sometimes can result in tests that do not ramp up to the number of users you expect or otherwise behave strangely.
User Capacity Analysis
How Many Users?
One of the most important goals of load testing is to find out how many users a particular website can handle simultaneously. For years, Load Tester has been the only product to give a direct, simple answer to that question. In the Load Tester 3.6 release the user capacity algorithm received a major overhaul, making the analysis more configurable, more flexible, and more accurate than ever before.
In this tutorial we’re going to look at some real-world load testing examples, and discover how user-capacity analysis tells us exactly how many users the web sites can handle.
Before We Begin
There are … Continue reading »
Checklist: Is your Load Test ready to run?
Here are a few quick pointers for checking your Load Test, to see if you are ready to run. Feel free to check back, as this list may be updated from time to time.
Test Planning:
Have the appropriate parties been notified of the test?
Do any of the servers have scheduled jobs during the test window? Automatic backups or other maintenance windows that are scheduled during normal down-time or idle-time can have surprising results during a high volume test.
Is the firewall going to be an issue? When using a small set of external IPs to generate load, make sure the firewall administrators … Continue reading »
Moving Load Tester™ To A New Computer
If you’ve installed Load Tester™ on a workstation, and are in the process of upgrading to a new workstation, you may be wondering how to move your Load Tester™ installation between the workstations. For version 4.0, this is not a difficult process, and generally can be completed in four steps:
Install a copy of Load Tester on your new workstation. New installers are available at www.webperformance.com/download
Copy the .WPT files from the old workstation (if they are not already saved on a network share). These files contain your recorded & configured testcases, as well as load test results.
Transfer your License … Continue reading »
Load Testing from the Cloud
Over the last few weeks I’ve been tinkering with Amazon’s EC2 service, setting up a Load Tester load engine AMI and running tests from cloud instances. Our conclusion is that cloud engines can be useful, but there are some things you need to be careful about because they can cause subtle problems or even invalidate your test.
Getting Started
You’ll need to follow the Amazon instructions for getting set up on the service, as laid out in the Getting Started Guide. This is a somewhat non-trivial process that involves generating an X.509 certificate, and an SSH … Continue reading »
