Response Testing in Software Testing

Software applications are developed to provide some specific service to the customers. When an end-user uses a software product/application between the software and the user, a request-response interaction takes place. This request-response interaction is one method of communication between users and systems or multiple systems in a network. When one request has been made for some action it excepts some responses for it. In this scenario response provided time matters more as it is one of the most important factors in deciding the software performance and indirectly overall software quality. 

This article focuses on discussing the following topics in detail:

1. Introduction to Response Testing.
2. Measurement of Response Testing.
3. Procedure for Estimating Response Testing.
4. Types of Response Metrics.
5. Important Response Time Values.
6. Response Testing Tools.

Introduction to Response Testing

Response Testing, also called response time testing, is the measurement of time between the data collected by the server and data given back to the client. It is the proportion of time taken from the moment of the client’s request is sent to the moment of the server’s response. The estimated time between the operation is called response testing.

• For example, If the user is using internet banking and wants to know the available balance in the account, hence clicked on the ‘Show Available Balance’ button and the time taken in between to display the available balance on the screen after getting the details from bank server is called as response time. 
• Here the request was to display the available balance in the bank account and the response was getting the details of the available balance in your account, and the time taken from request to response is called response testing.

Response time testing operation begins when the client sends a request and the operation ends when the server states that the request has been completed. 

Measurement of Response Testing

Response time is measured with the help of test tools. The test tools track the time of input and output requests. The response timing of each application may differ from one tool to another.
After the client requests an application, the test tools inform the application programming interface, allowing it to record the time taken. The variation in the load of any application may affect the response. If a load of any application is more, then it takes more time for response.

Procedure for Estimating Response Time

The steps to follow to estimate the response time is:

1. Determine test parameters: While one wants to perform a response time test, one needs to identify different factors and various parameters based on which the testing will be performed. Parameters can be the speed of network bandwidth, establishing web/app connectivity, response to download and upload, etc. These parameters are variables that can be changed during the experiment based on the scenario.
2. Perform response time test: When the parameters are set up including various variables and controls one is ready to go for the performance test. By using different variables and controls perform the test and check the response time of the application. When response time does not cross the average response time limit then conclude that the application is responding very well and quickly.
3. Record the result: During the test and after the test, keep a track of your results which can be used for further findings, also it can help in future tests. The maintained log acts as proof of the application’s response time to the higher authorities and finally to the end-users.
4. Identify errors and success: After the test is completed and the log is recorded perform an analysis to check whether the test was successful or not. Which points need to be taken care of and which instances acted very well. Even the final status report can be delivered to higher management or to the client based on their requirement.

Response Time 

Types of Response Metrics

The following are the different types of response metrics:

1. Average response time: Average response time is the meantime recorded for a server in each round trip. The average response time comprises the loading time of XML, CSS, HTML, javascript, etc. Hence, the average response time gets affected when the components are slow in a system.
2. Peak response time: It helps in pointing out the problematic and slow components in a system. It handles all the troublesome components in the system efficiently.
3. Error rate: It is a feature of response metrics that is responsible for handling the mathematical calculation. The error rate feature displays the percentage of error present in the system. 

During response testing, there are other response time metrics, which are considered for measurement like

1. Hardware utilization: This is used to measure how much hardware computing power requests and response time are used. It helps to measure the viability of current hardware systems and checks if hardware upgrades are required.
2. Size of data in and out: It tracks the size of each batch of requests to the server and the number of responses created by the server. 
3. The number of requests per second measures how many requests an application or website receives each second. More requests per second can result in slower response times. 

Important response time values:

1. 0.1 second: The applications responding at 0.1 seconds are considered perfect. It is an ideal time and this time means the application is not facing any interruption.
2. 1.0 second: If any application system is responding at 1.0 seconds then this response is acceptable, although it should not exceed 1.0 seconds. Users may face some delays while working on the application. However, they will not face any breakdowns.
3. 10 seconds: 10 seconds is the maximum time limit and it should not exceed. If the response time value exceeds 10 seconds then the user may face long-time interference. Users may uninstall the application.

Ways to Improve Server Response Time :

1. Code Efficiency :

• Code should be very efficient.
• The time complexity and the space complexity of the code must take it into the concern.
• Build the code in an effective manner to run or load it in few seconds.
• This is an important factor for well built technically sound websites or web application.

2. Database Optimization :

• Use efficient queries to execute the results.
• Use more of PL/SQL functionalities to execute it in lesser time.
• Avoid repetition of the details.
• There should be effective backend testing.

3. Deploying to cloud :

• Deploying the application to the cloud will have faster response time
• Response will be quick since there are many servers.
• We can access it anytime without any interruption.

4. Increasing the Resources :

• Increasing in number of instances will result in quick response.
• Increasing in number of servers, CPU etc., will also result in good response time.
• We can avoid having the interruptions and don’t need to wait on same page for longer time.

Response Testing Tools

There are countless numbers of response time testing tools available in the market. The important and famous response testing tools are as follows:

1. Load Runner: 

• It is a performance testing tool that tests software application behavior and performance under load.
• It is provided by Microfocus.
• Based on the load testing script it performs load analysis of the software.
• It is not available in open-source format.

2. JMeter:

• It is a performance testing tool that supports 100% Java programmed desktop applications.
• It is provided by Apache.
• It can work with a number of protocols like HTTP, HTTPS, TCP, SOAP, FTP, LDAP, IMAP, SMTP, etc.
• It is available in open-source format.

3. AEM:

• AEM refers to Adobe Experience Manager.
• It is a framework that is used to test component UI.
• It is provided by Adobe.
• t provides tools for automating test cases.

4. Google’s PageSpeed Insights:

• It is the free tool to find and test factors slowing down your web application
• It is provided by Google.
• It performs the speed test of the application and gives a score between 0 to 100.
• It is available in open-source format.

Advantages of Response Testing in Software Testing:

• Helps in verifying system responsiveness: Response testing helps in verifying the system responsiveness in terms of how quickly the system responds to user inputs, network delays, and other factors that affect the system’s response time.
• Identifies performance bottlenecks: This type of testing helps in identifying performance bottlenecks and critical areas that require performance optimization.
• Ensures end-to-end functionality: Response testing verifies the end-to-end functionality of a system, including network connectivity, load balancing, and backend processes.
• Enhances user experience: By testing the response time of a system, response testing helps enhance the overall user experience.
• Helps in load testing: Response testing can be used for load testing, which is essential for determining a system’s performance under heavy load.

Disadvantages of Response Testing in Software Testing:

• Not enough to guarantee system performance: Response testing is not enough to guarantee system performance as it only tests a single aspect of the system’s behavior.
• May not uncover all performance issues: While response testing helps in identifying performance bottlenecks, it may not uncover all performance issues, especially those that are hidden in the system.
• Requires specialized tools: Response testing requires specialized tools to measure and analyze system response time, which can be expensive.
• Time-consuming: Response testing can be time-consuming, especially when testing a large system with multiple components.
• Can be affected by external factors: Response testing can be affected by external factors such as network latency, which can make it difficult to determine whether the system is slow or the network is slow.