Performance Testing

Performance Testing Tutorial: What is, Types, Metrics & Example

Evaluation of Performance
A software application’s speed, response time, stability, reliability, scalability, and resource usage are all evaluated during the performance testing phase of the software testing process. Performance Testing is a subset of Software Testing. The primary objective of performance testing is to locate and remove any performance bottlenecks that may exist within the software application being evaluated. Performance testing is a subfield of performance engineering that also goes by the name “Perf Testing.”

The performance of a software application is the primary focus of Performance Testing.

The speed at which the application responds is one of the factors that are taken into consideration.

Scalability is the ability of a software application to manage a maximum number of concurrent users.

Determines whether or not the application can remain stable under a variety of load conditions.

You will pick up the following by the end of this guide:

Why do Performance Testing?

A software system’s supported features and functions are not the only thing to take into consideration. It is important to consider the performance of a software application in terms of its response time, reliability, resource usage, and scalability. The objective of performance testing is not to locate bugs but rather to remove bottlenecks in the system’s overall performance.

Performance testing is carried out so that stakeholders can obtain information about their application’s rate of operation, level of consistency, and degree of scalability. More importantly, performance testing reveals what aspects of the product need to be enhanced before it can be released to the public. Without performance testing, software is more likely to have problems such as poor usability, sluggish performance even when multiple users are accessing it at the same time, and inconsistencies when running on a variety of operating systems.

Through performance testing, it will be determined whether or not their software satisfies the requirements for speed, scalability, and stability under the expected workloads. Applications that are released into the market with poor performance metrics as a result of nonexistent or poor performance testing are likely to acquire a negative reputation and fail to meet the sales goals that were anticipated.

In addition, mission-critical applications such as space launch programmes or life-saving medical equipment ought to undergo performance testing in order to guarantee that they can operate continuously and error-free for extended periods of time.

Dunn & Bradstreet reports that approximately 59 percent of companies on the Fortune 500 list experience an average of 1.6 hours of downtime each and every week. If we assume that the typical Fortune 500 company has at least 10,000 workers and pays them $56 per hour, then the labour component of the downtime costs for such an organisation would be $896,000 each and every week. This would translate to more than $46 million each and every year.

It is estimated that the search giant will lose as much as $545,000 due to the fact that Google.com was unavailable for only five minutes on August 19, 2013.

It is estimated that businesses suffered revenue losses equivalent to $1100 per second as a direct result of a recent outage experienced by Amazon Web Services.

Testing for performance is crucial for this reason.

Types of Performance Testing

Load testing examines an application to determine how well it will function when subjected to the anticipated number of users. Before the software application is made available to users, it is necessary to locate and eliminate any performance bottlenecks that may exist.

The purpose of putting an application through what is known as “stress testing” is to evaluate how well it copes with high levels of data processing or traffic. The goal is to determine the point at which an application becomes unworkable.

Testing for endurance is carried out to ensure that a software application is capable of withstanding the anticipated load for an extended period of time.

Testing on spikes examines how the software responds when subjected to sudden and significant increases in the amount of work being done by users.

Testing on a volume—Under the heading of Volume Testing, a large number of. A database is populated with data, and the behaviour of the software system as a whole is observed and recorded. The purpose of this test is to evaluate how well a software application performs with varying amounts of database traffic.

Testing for scalability has the purpose of determining whether or not the software application is capable of “scaling up” to accommodate an increase in the number of users. It is useful for planning the addition of capacity to your software system.

The Most Frequent Issues With Performance

The majority of performance issues are related to issues of slowness, including response time, load time, and poor scalability. In many cases, speed is one of the characteristics that is considered to be the most important. An application that runs slowly will cause it to lose potential users. The purpose of performance testing is to ensure that an application runs quickly enough to hold the attention and interest of a user. Take a look at the following list of typical performance issues and take note of how speed is a contributing factor in many of these issues:

Long load time: The “load time” refers to the normal amount of time it takes for an application to start up for the first time. In most cases, this ought to be kept to a bare minimum. Although it is impossible to get some applications to load in less than a minute, load times should be kept as short as possible whenever it is possible to do so.

Poor response time: The term “response time” refers to the amount of time that passes between when a user enters data into an application and when the application produces a response to the user’s input. In a general sense, this should not take very long. Again, if a user is required to wait for an excessively long period of time, they will lose interest.

A software product is said to have poor scalability if it is unable to handle the anticipated number of users or if it does not accommodate a user base that is sufficiently diverse. It is important to carry out load testing in order to ensure that the application can support the anticipated number of customers.

The term “bottlenecking” refers to obstructions within a system that bring about a decline in the performance of the system as a whole. When coding errors or problems with the hardware cause a decrease in throughput under certain loads, this phenomenon is known as bottlenecking. A single problematic segment of code is frequently to blame for bottlenecking. Finding the part of the code that is causing the bottleneck and attempting to fix the issue there is the most important step in resolving a bottlenecking issue. In most cases, bottlenecks can be eliminated by either improving the performance of currently running processes or installing additional hardware. The following are some examples of common performance bottlenecks:

Common Performance Problems

Although there is a lot of leeway in terms of the methodology used for performance testing, the end goal of these kinds of evaluations always stays the same. It is possible to demonstrate that your software system satisfies a number of pre-defined performance criteria with its assistance. Alternately, it can be used to facilitate the performance comparison of two software systems. In addition to this, it can assist in locating components of your software system that hinder its performance.

Listed below is an example of a generic procedure for carrying out performance testing.

  • Image of the process of testing performance
  • Determine the environment in which testing will take place. You should be familiar with your production environment, as well as the testing tools that are at your disposal. Before you begin the testing process, be sure that you have a thorough understanding of the specifics of the hardware, software, and network setups that will be employed. It will assist testers in developing tests that are more effective. In addition to this, it will assist in
  • identifying any obstacles that the testers may face when carrying out the performance testing methods.
  • Determine the criteria for accepting the performance as acceptable. This should include goals and restrictions for throughput, response times, and resource allocation. In addition to this, it is essential to establish project success metrics that are independent of these goals and restrictions. Because the project specifications frequently do not offer a sufficiently diverse selection of performance benchmarks, testers should be given the authority to establish performance criteria and goals. There may be no evidence at all in some cases. Finding a comparable piece of software to benchmark your own efforts against is recommended whenever it’s practicable to do so.
    Tests of functionality should be planned and designed. Determine how the usage is likely to differ among end users, and then select critical scenarios that should be tested for all probable use cases. It is essential to simulate a wide range of end users, to organise performance test data, and to sketch out the metrics that will be collected.
    Putting together the test environment’s configuration — Before beginning the execution, you need prepare the testing environment. Additionally, organise the many tools and resources.
    Implement the test design and make sure your performance tests are created in accordance with the test plan.
  • The tests should be run, which entails both executing and monitoring the tests.
    Analyze, make adjustments, and retest, then consolidate, analyse, and discuss the outcomes of the tests. After that, make any necessary adjustments, and run another round of tests to determine whether or not the performance has improved. Because the gains typically become less significant with each subsequent test, you should stop when the bottlenecking is driven by the CPU. After that, you might have the option of upgrading the processing power of the CPU.
  • Metrics for Evaluating Test Performance: The Monitoring of Parameters
    During performance testing, some of the most fundamental parameters checked are as follows:

Performance Testing Process

  • The amount of time that a processor spends actively executing non-idle threads is referred to as its “usage.”
  • Memory utilisation refers to the total quantity of a computer’s physical memory that is being utilised by various processes.
  • The amount of time that a disc is occupied by executing a read or write request is referred to as disc time.
  • The term “bandwidth” refers to the number of bits per second that are utilised by a network interface.
  • The quantity of bytes that a process has reserved for its own use and that cannot be shared with any other processes is referred to as private bytes. These are utilised in the process of measuring memory usage as well as memory leaks.
  • Committed memory refers to the amount of virtual memory that is currently being used.
  • Memory pages/second refers to the number of pages that are either written to or read from the disc in order to fix hard page faults. When code that is not part of the currently active working set is called up from somewhere else and fetched from a disc, a hard page fault has occurred.
  • Page faults per second refers to the overall processing speed of the fault pages by the computer’s processor.
  • This happens once again when a process needs code from outside of its working set.
  • CPU interruptions per second is the average number of hardware interrupts that a processor receives and processes each second. These interrupts can come from a variety of sources.
  • The number of average read and write requests that are waiting in line for a particular disc at any given point in time is referred to as the disc queue length.
  • The length of the output packet queue in the network is referred to as the network output queue length. When there are more than two people involved, there is a delay, and the bottlenecking needs to be eliminated.
  • The entire number of bytes transferred across the network in one second, including any framing characters that may be present.
  • The amount of time that passes between when a user initiates a request and when the first character of the response is received is referred to as the response time.
  • A computer or network’s throughput is the pace at which it gets requests per second.
    Amount of connection pooling refers to the quantity of user requests that are satisfied by connections that have been shared across multiple users. The number of requests that are successfully completed by connections in the pool directly correlates to the level of performance achieved.
  • The maximum number of sessions that can be active at the same time is referred to as the maximum active sessions.
  • Hit ratios refer to the number of SQL statements that are processed by the cached data rather than by costly I/O operations. This metric is related to the hit ratios. When it comes to resolving problems with bottlenecking, this is a good place to begin.
  • Hits per second is the number of times a website is accessed in one second while being subjected to a load test.
  • The quantity of data that can be rolled back at any one point in time is referred to as the rollback segment.
  • Locking of databases and tables requires close monitoring and fine-tuning. Locking of databases and tables must be done properly.
    Top delays are tracked in order to ascertain which wait times can be shortened in relation to the rate at which data is retrieved from memory.
  • Thread counts allow the overall health of an application to be evaluated based on the number of threads that are actively executing within the programme.
  • The term “garbage collection” refers to the process of giving unused memory back to the operating system. Monitoring is necessary to ensure that garbage collection is carried out effectively.

Performance Testing Metrics: Parameters Monitored

Check that the response time does not exceed four seconds even when one thousand people are using the website at the same time.
When the network connectivity is slow, it is important to check that the response time of the Application Under Load is within an acceptable range.
Determine the maximum amount of concurrent users that the application can support before it becomes unstable.
Check how long it takes the database to execute by simultaneously reading and writing 500 records.
In times of peak load, make sure to check how much the application and database server are using of both CPU and memory.

Example Performance Test Cases

Check how long it takes the application to respond under different levels of load: light, normal, moderate, and heavy.
Concrete values are substituted for nebulous concepts like acceptable range and heavy load when the performance evaluation is being carried out in its true form. Performance engineers determine these values by taking into account both the business needs and the application’s existing technical landscape.

Instruments for Evaluating Performance
On the market, performance testing tools can be found in a broad variety of forms and configurations. The testing tool that you use will be determined by a wide variety of criteria, including the kinds of protocols that are supported, the cost of the licence, the hardware requirements, the platforms that are supported, and so on. The following is a list of testing tools that are widely utilised nowadays.

Performance Test Tools

  • LoadNinja is completely changing the way that load testing is done. This load testing tool is hosted in the cloud, and it enables teams to record and rapidly playback extensive load tests. These tests can also be conducted in real browsers at scale, without the need for complex dynamic correlation. Teams have the ability to expand their test coverage while also reducing the amount of time spent load testing by more than 60 percent.
  • HeadSpin gives its consumers access to the most advanced performance testing tools in the business. The performance testing capabilities of the HeadSpin Platform enable users to optimise their digital experiences by discovering and resolving performance issues across applications, devices, and networks. This may be done by testing the platform’s performance. HeadSpin offers actual, real-world data, which helps remove uncertainty from the thousands of devices, networks, and places that are in use. Users are able to take advantage of strong
  • AI capabilities to automatically uncover performance issues in testing before such issues have an impact on users.
  • The most widely used performance testing tools on the market today are made by HP and go by the name
  • LoadRunner. This tool has the capacity to simulate hundreds of thousands of users, thereby subjecting apps to real-life loads in order to assess how they behave when subjected to expected loads. A virtual user generator is included in Loadrunner, and its purpose is to recreate the behaviour of actual human users.
    One of the most popular tools for performing load testing on web and application servers is called Jmeter.