LoadView FAQ

Common Technical Questions

How do you ensure the cloud machines are not a bottleneck of testing?

When you calibrate a test, we calculate how many virtual users per machine can safely run without over-burdening the CPU of each virtual machine. This is how we arrive at the number of virtual users per virtual machine. Depending upon the task type, and whether the tasks use a real browser or not, there can sometimes be a small spike at the beginning of a task as a browser such as IE opens, clears cache and starts the script. Typically the average CPU usage is much lower than 100%, so we do allow you to increase the number of virtual users per machine to get a higher utilization of each machine, but if you change this number we cannot guarantee the cloud machines will not max out CPU usage and become a slight bottleneck of the test.

Where is the load generated from?

LoadView tests run in the cloud. When you set up a load test you can select from a number of cloud based locations from Google and Amazon around the world. As Google and Amazon expand their available locations we will continue to add these options to LoadView.

Can you Load Test complex web applications that require a login or use AJAX, Silverlight or Flash?

You can set up basic single page load tests or complex multistep scripts. Using the EveryStep script recorder you can simply point and click on a website, fill out forms, click buttons and navigate through the website. All user interactions can be recorded, including Ajax, html5, Flash or other Rich Internet Applications (RIAs).

Do you use real or simulated browser?

Both. You have the option of selecting simple GET requests or of using a real browser to actually download, render and interact with your website during a test. The differences may seem subtle, and a full browser may not always be required for every test, but particularly when a website has advanced user interfaces with RIA, rendering the test in a full browser will show a much different result, and be more representative of real users interacting with the website.

What is the User Behavior Delay?

User Behavior is how we define the delay between interactions. If you are trying to simulate real users on a web page, you may want them to pause for a random number of seconds when a user might stop to read text on a page before continuing. Setting this value close to zero may not emulate real browser behavior, but will place much higher load and stress on your system.

How can I simulate my real users?

Using EveryStep script recording tool you can point and click through your website just as a real user would. EveryStep records your actions and allows you to upload those recordings to be replayed by a virtually unlimited number of simultaneous users.

How can I create as much load on a server as possible?

It depends upon what type of load you are talking about.
Using an HTTP/s type task you can easily send thousands of simultaneous GET requests to your webserver, and increase the number of simultaneous users as you wish.
Setting the User Behavior delay to 0 will run the tasks as fast as possible, rather than introducing a delay to simulate users reading content on the page.

What data do I get back as a result of the test?

After the test runs, the results of every session that was run in the test is available in the test history. Graphs of test response times are generated as well as a variety of reports including total sessions generated, response times by location and by individual task.

What is the maximum number of users can you generate?

Because LoadView runs in the cloud, there is virtually no limit to the number of users that can be generated for a load test. The tests are theoretically limited by the total number of virtual servers available from the cloud providers at any given point and also by the cost to lease those servers from providers such as Amazon and Google. Given enough advanced time to setup a test, you should be able to generate as much load as you need to complete a proper load test.

How can I ensure that there is no throttling or resource limitation on load generating side?

When you setup a load test, it is automatically calibrated with a machine in the cloud. This calibration sets the default limits of load that can be generated per virtual machine so that the virtual machines will not be a bottleneck.