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Load Testing Blog

The Complete Guide of JMeter Controllers

In this blog post we are going to look at several JMeter Controllers, specifically:

This is not an exhaustive list of controllers that JMeter offers but these once will give you a clear insight into how controllers are integral in defining load testing scenarios and how without them you will struggle to build complex and indicative load tests.

Technically JMeter has two types of controllers and these are categorised as Samplers and Logical Controllers, the controllers we are looking at in this post are the Logical Controllers that allows you to customise how JMeter delivers requests to meet your load profiles.

Let’s look at the logical controllers with some examples of how they can be used, our tests will consist of Dummy Samplers as this is the simplest way to demonstrate how the various Controllers work. You can follow along each example by downloading the JMX here.

OctoPerf v12.2 - Flexible license sharing, improved VU validation, XPath and JQuery

We've been working a lot behind the scenes for this release because we wanted to address the license sharing issue. Up until today it was only possible to ask us to share the license for you and sharing could only share every license you own. We had to completely refactor the way we handle licenses to allow you to decide on your own to share all or a fraction of your subscriptions.

But that's not all, we also worked on a VU validation with multiple iterations. XPath and JQuery processors were only available when importing from JMeter but now you can create them directly in OctoPerf's UI and use them in your automatic correlation rules. And many other features that we will highlight in this post.


Share a license

The main course is the new license sharing system. It used to be possible to share a license by asking our support team to share all your licenses with another account, but even if we always answer fast that was not convenient and even worse, you had to share all your licenses with the new account.

For these reasons, we've worked on a system that is fully flexible, allowing you to share some or all your subscriptions with another OctoPerf account:


A complete look at JMeter's FTP and SSH SFTP samplers

While the File Transfer Protocol is one of the original protocols used in the early adoption of the internet it remains a fundamental part of modern computer networks.

In this post we will look at the way the JMeter can support you in performance testing FTP and SFTP.

SFTP is a more recent development to provide a layer of security over the original protocol to make it more suitable for the modern internet and is different to FPT in many ways.

Whilst SFTP is considered more appropriate for modern systems there are still many applications that rely on, and implement, FTP and therefore we will look at how we can test both.

If you want to follow along, a JMX file containing all the steps detailed below can be downloaded here.

Risk Assessment In Performance Testing

Performance Testing coverage needs to be defined from the application under tests functional requirements and this does not change regardless of whether you are following an Agile or a more Planned approach.

The Risk Assessment process defines what performance testing needs to be executed and the order in which this should be approached, the reason we use the functional test requirements for definition of coverage as these functional requirements define what the system does whereas the non-functional requirements are what you use to measure your tests against when you execute them.

As discussed the Risk Assessment is a way of identifying where your performance testing effort should be focussed and prioritising the order in which your performance tests are written and therefore executed so you ensure that you are focussing on the riskiest, from a performance perspective, aspects of the system first; we will expand on what we mean by riskiest later in this post.

A Risks Assessment should be done as early in the project or sprint, if you are working in an Agile methodology, as is possible to maximise its benefits.

The first thing we will discuss is the differences between Agile and Non-Agile Risk Assessment as this is an important concept but only as far as what is assessed and when, the principles of how and why we carry out a risk assessment will become clear as you read this post and remain the same regardless of your approach to development.

Troubleshoot your tests

Preparing resilient tests can be a challenging process when you do not know where to start. We will cover this in this guide, from the virtual user validation to smoke testing. And then analyzing the most common errors and how to fix them. Note that we also recommend reading this other guide, it can greatly help understand the analysis and report engine of OctoPerf.

As a final note before we start, as much as you might want to jump to the relevant section of this guide, I strongly recommend you take a few minutes to read the next section since proper test preparation is essential to a strong error analysis later.