Load testing

17 March 2021 by Laura Hill

Are you planning for a change in your learning management system? 

Will you be running fully online exams at your next assessment period, migrating your system to the Cloud or upgrading to the next version of Moodle? With any change in the system or traffic profile, is your LMS resilient, resourced sufficiently and ready to withstand increased numbers of students or stakeholders? Vital questions for every academic institution over these next few weeks and months.

Catalyst can provide vital reassurance and certainty of your learners' experience by testing in advance of new releases and changes to normal site traffic and load patterns.

What is your LMS maximum capacity of traffic?

Our load testing services enable you to find out the maximum capacity of traffic and load that your website can serve. Being informed about the performance and stability of your LMS is increasingly crucial. By replicating real website traffic behaviours Catalyst uncovers issues in advance of a major release or announcement ensuring the system is going to deliver what is required of it. We simulate various real life scenarios and load patterns to measure the impact on your LMS and it's underlying infrastructure.

Real-world traffic conditions

With load tests running Catalyst will support your technical teams to analyse the infrastructure which your system is hosted upon, we examine the metrics and insights available and achieve test accuracy by emulating real-world traffic conditions that can be tweaked and changed easily from one test to the next. The goal is to identify and present bottlenecks or breakpoints so as these may be resolved or rectified through whatever means are necessary. If there is potential to resolve through tuning and configuration of the Moodle system, then Catalyst's world leading Moodle expertise can assist - or if it is found the infrastructure is insufficient to meet demand our team of AWS certified cloud experts are on hand to provide solutions to such capacity problems.

By applying a range of load tests built around common and known system stressing user journeys, we are able to benchmark the results against our extensive experience running similar tests with our many clients against a myriad of hosting scenarios and end user requirements.

We have a range of load tests available immediately, with soak tests - to load the system for long periods of time, or pressure tests to emulate the fast in rush of users logging into a site in a strictly time-bound exam scenario. We are able to layer tests so as to ensure that your system can continue to serve its daily traffic requirements whilst also encountering a new and previously unseen traffic profile.

Load testing is used to uncover the limits of your LMS system. Catalyst utilise Jmeter to carry out the scripted load application. As noted above a number of ready to go tests are available in our load testing service, though we are able to develop custom load test scripts and user journeys if required.

  • Stress testing, can be described as a type of negative testing with the goal of observing and analysing the system’s stability and recovery after failover or crash. Overloading the application beyond its expected capacity. 
  • Spike testing the web application means it will be subjected to quick and progressively increasing load volumes, beyond what is expected, for short amounts of time. 
  • Soak testing or endurance testing subjects the web application to the usual anticipated load over a long period of time with the objective of finding out how the system behaves. Potential memory leaks or odd behaviour are equally important to pinpoint. 

Catalyst has specialist load testing expertise on our team in all locations globally. We have worked with many higher education institutions around the world with tried and tested models that have been improved iteratively to get as. close to real life scenarios as is possible.

Open University

We offer bespoke load testing for institutions with more complex requirements. For our client, Open University, Catalyst load tested their current stack for random aspects of site navigation. To give an example, should user 1 wanted to log in and go to a forum to be part of a discussion, user 2 to submit an assignment and user 3 to take a quiz. Catalyst provided a month of load testing and development. The first phase included testing the OU’s current Moodle, then creating a new Moodle hosted on AWS Cloud. We run the tests repeatedly in collaboration with engineers at the OU as they worked to add more infrastructure resources and changing the configuration parameters until a suitable scaling and tuning state was reached. Thus giving peace of mind that on day one after a major cloud migration, the system was ready and fit for purpose.

We also utilise load testing to help with scaling configurations to deliver cost savings to systems based in the cloud by developing a clear horizontal and vertical scaling plan, once a client has migrated to the Cloud such benefits are realised, but it is important to utilise them effectively. No on call engineer wants to be notified late at night that a system is down because it was under resourced, and no budget owner wants a very large cloud hosting bill at the end of the month where lots of wastage is evident. Only robust load testing of the type Catalyst provide can ensure this is correct in advance of release.

Dublin City University

For our partners Dublin City University we provided a series of load testing over 1.5 days consultancy. Using our existing scripts and changing the parameters effectively, this comprised 3 load testing exercises. 

The mix of tests included thousands individual students submitting assignments and further thousands taking quizzes simultaneously, all of which were observed and monitored to see how effectively the LMS coped. Read our case study on Dublin City University’s e-assessment solution and Cloud migration. 

University College London

With our partners University College London the primary objective of the performance and load testing exercise was to confirm that the site can properly withstand and function under three different scenarios of load dictated by our standard load testing suite.

After discovering that ClamAV was responsible for issues we encountered while testing quizzes, the second UCL load testing phase covered re-running the highest load iterations with fixes in place for ClamAV - iterating over and over until the tests passed.

The current results can clearly speak for themselves with our partners UCL, who are now supporting 48,000 active students upon the busiest (by page loads views day) Moodle instance in the UK.. The university was receiving 700,000 page views a day, prior to Covid and since moving to Cloud is now frequently receiving 1.5 million page views a day. 

Data driven strategic decisions 

We provide each client with a simple and easy to read report to enable them to make data driven strategic decisions.

The reports we compile include APDEX scoring, showing the number of end users who will have received a positive and responsive experience, vs those users who may have encountered slowness or even error messages in certain cases. The report includes dashboards containing graphical representation for response time ranges. An example of this will be how many click responses were under ½ second and how many over 1 or 1.5 seconds. 

Our report shows each and every request and how long it has taken. We can analyse the data, combined with data from your system and your infrastructure monitoring to identify exactly where an issue is and resolve it. Quizzes on Moodle, for example, are often linked to slow page loading. Slow page loading is a particularly concerning issue for timed online assessments. 

The outcome is incredibly valuable insight, peace of mind and assurance that your web application will not falter when facing high concurrency events or significant changes in site activity. Load testing protects your learner users, your institution and your brand. 

Contact us today to discuss how we can support your new or upcoming digital initiatives with our load testing services.