Differences between Performance vs. Load vs. Stress Testing

Performance Testing

It is a software testing process used to test the response time, speed, stability, reliability, scalability, and usage of a software application under a particular workload. The primary purpose of performance testing is to identify and eliminate the performance bottlenecks in the software application.

It is done to offer stakeholders with information about the application regarding speed, scalability, and stability. Without Performance Testing, the software will suffer from issues such as: running slow, inconsistencies across different operating systems.

Performance testing determines whether the software meets speed, stability, and scalability requirements under expected workloads. Applications sent to the market with low-performance metrics due to nonexistent or low-performance testing do not gain a bad reputation and fails to meet sales goals.

Load Testing

Load testing identifies whether the infrastructure used for hosting the application is sufficient or not. It is used to find if the application’s performance is sustainable when it is at the peak of its user load. It tells how many users the application handle and the scale of the application required in terms of hardware, network capacity, etc. to access the application. It helps you identify the maximum operating capacity and any bottlenecks and determine which element is causing degradation.

It is done under controlled lab conditions to compare different systems’ capabilities or accurately measure a single system’s capabilities. It involves stimulating the user’s load for the target application. It helps you to determine how your application behaves when multiple users hit it simultaneously. The main aim is to define the amount of work a system can handle without performance degradation.

Stress Testing

Stress testing checks the stability and reliability of applications. Stress testing aims to measure applications’ error handling capabilities and robustness under hefty conditions and ensure that they do not crash under tight situations. It tests beyond regular operating points and evaluates how the applications work under extreme conditions. Stress Testing is also called Endurance Testing. Under this type of testing, AUT is be stressed for a short period to know its withstanding capacity. The main use of stress testing is determining the limit at which the system or software or hardware breaks. It checks whether the system demonstrates effective and efficient error management under extreme conditions.

Performance TestingLoad TestingStress Testing
It is a superset of stress and load testing.It is a subset of performance testing.It is a subset of performance testing.
It helps to set the standards for the application.It helps to recognize the system’s upper limit, established the app’s SLA, and check how the system can handle a heavy load.It helps to check how the system behaves under extreme loads.
It aims to get an indication of how an application behaves under normal parameters.The main aim is to generate increased load on a web application.It aims to ensure that the servers don’t crash under a sudden high gear for a considerable duration.
The load limit is both above and below the threshold of a break.The load limit is a threshold of a break.The load limit is above the threshold of a break.
Example: Checking concurrent users, HTTP connections, or checking Suitable response time.Example: Test a word processor by making a change in the large volume of data and testing a printer by transferring heavy data.Example: shut down and restart ports of a large network.


When to do Performance Testing?

It is done to check the performance of the website servers, network, and database. If you are using an agile software development approach, then you need to test the application continuously.

When to do Load Testing?

It is performed to determine how many users the system can handle. You can check out different scenarios that let you focus on other parts of your system, such as the home page or checkout webpage on your website for web load testing. It helps you to determine the load builds and sustains in the system.

When to do Stress Testing?

It is very crucial to test the capacity of the system endurance. This also helps you prepare for unexpected traffic spikes and gives more time and resources to fix any bottlenecks.

Is it unfair to perform Stress testing and Load testing at the same time?

It is a common question in many interviews that is it unfair to do stress testing and load testing at the same time? The answer is ‘No.’ It is not unfair to do stress testing and load testing at the same time.

Does it require to implement performance testing?

Performance testing does require you to know to code. Having knowledge of programming is an added advantage.

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