Load Testing - Applications and Setting Up
If there’s one thing every successful developer does is, it is testing. They ruthlessly test their applications and websites to make sure that it can perform up to their expectations. Every great developer or development company performs frequent load tests on their applications to make sure it is free of any errors or bugs. Testing a product is a learning process.
This blog digs one level deeper from our previous blog on Basics of load testing and takes you through the application of load testing and the setting up process.
Table of contents
- Revisiting Load Testing
- Practical application of load testing
- Prerequisites for load testing
- Steps to perform a Load test
Revisiting Load testing
Before we proceed with the application of load testing, let us quickly revisit what it is from our previous blog. Load testing is a way to test the performance of your systems and applications with a pre registered load. It is usually done to determine the speed and practical functionality of the application.More importantly, it is done to make sure that the theoretical calculations of your system meet the practical uses.
Practical application of load testing
Consider this scenario - Partech is developing an application that is similar to an online chat application ( whatsapp, wechat etc.. ). Partech’s consumers can use this application to create common groups, to chat with their family and friends.
Let us assume that this application can manage a 50 persons group and have a response time of 1 second. This is a theoretical assumption for your application.
Now there are two ways to test this theory for Partech -
- Send it out to a bunch of people and ask them to use this application
- Perform a machine operated load test
While the Option 1 might sound beneficial, it is harder to perform and calculate results. So Partech decided to go with Option 2.
They use a load testing application to simulate the action of 50 concurrent users ( people who perform the same function in your app at the same time ) in your application. Once they set it up and set up the right systems for measurement - it’s action time.
Let’s say that the test returns a response rate of 3 seconds. Patech needs to upgrade certain areas of their application or remove certain areas of redundancy. If the test returns a response rate less than or equal to 1 second, the application is quite good..
This is the power of load testing where theoretical expectations match your practical results with minimal efforts.
Prerequisites for load testing
There are a few things you might need before starting the process of load testing your application. Here are they -
- A load testing application
- Realistic Goals
- Real-life benchmarks
- Dedicated testing environment
A load testing application
This dedicated application enables you to perform load tests on your application. You can plug your application into it and pull the right knobs to get results. But sometimes a load test requires the addition of code or the isolation of a certain part of an application. This is when you need a dedicated team of developers to perform your Load test.
After deciding on a load test application, you need to set realistic goals for your test. Now is your time to think about the features your users would benefit the most from. You should also start testing the features that will be commonly used by your consumer. You need to find answers to questions like will they use different devices to login to your application or what function truly matters to them?
Think about questions like these before you set up a realistic goal for your load test. If you feel that your consumers will use a variety of devices, mix the characteristics up in your load test to keep it varied.The idea is to keep the goal of your tests as realistic as possible!
In a real-life scenario your load tests will not always start from zero. You will always have a number of people using your application before more people join in. You need to set a benchmark that mimics the real-life usage of your application. This comes with a deep understanding of your application and its uses. Run your application with a minimum load before you start testing it with further load.Always make sure that your benchmarks are an average of the real-life uses of your application.
Dedicated testing environment
If you have 2 servers for your application in a commercial use, your test must also have 2 servers. If your application has 4 servers in a commercial environment, your tests must also contain 4 servers.
Here’s the simple idea: Your test environment must always be similar to the production environment. Only then can all your tests results be considered as valid.
Here is how a load test is performed in a working environment
Steps to perform a load test
Here are 6 steps to perform a load test for your application/software. These steps serve as the chronological layers to build up a great load test. It may slightly differ, based on your application and consumer demands.
Minimum load test acceptance criteria
You should always state the minimum criteria that you would accept as a result for your load test. This can be a theoretical prediction or a value that arises from a previous load test. But this number should serve as a minimum acceptance criteria for your load test.
Commercial scenarios that needs to be tested
Let’s consider the example of the chat application that we’ve mentioned before. You need to have a deep understanding of your application to identify commercial scenarios where it will be used heavily. Will it be used by a team inside an organization (Slack) or will it be used for communication between friends and family (Whatsapp). Your Primary goal must be to find out how this application will be used in the field.
A Predetermined work-load model
Once you have a commercial scenario, you can also create a predetermined work-load model for your application.Here’s an example: Let’s revisit the chat application model we mentioned at the beginning of the post. Let’s say that one user goes out and sends a random text on a group. Or maybe he goes on to a group and asks a question. After he asks something, a number of users will log into the application to answer the questions. A person visits a group when someone has sent a message in it.
Design and execute the load tests
Finally you need to identify the areas and functions that need to be tested before diving into the test. Once that is identified, you can select a test environment and fire off your tests.
Analyze the results and create detailed reports
Once the tests are done, you can take the outputs and create detailed reports for better understanding. They will help you analyze what works better.
Identify areas of Improvement
As we have mentioned above, you need to identify areas of improvement for your load tests after you receive the results. This is the final step of your load test. If your test has failed: repeat from step 1 to step 8, while omitting steps 2 and 3.
Load testing is something that you need to implement at every stage of the development process.This will save you tons of time and resources over the long run.