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What is Load Testing?

What exactly is a spike test? How does it work?

A spike test is a kind of load test. It’s used to verify whether or not a system is stable during certain load spikes. An example of a spike test would be having multiple employees sign into a company portal all at the same time—which would create a spike in usage. This isn’t really an expected condition where the level of load stays the same, but still a situation that can occur and needs to be accounted for.

What is a stress test?

A stress test is similar to a load test, but different in the respect that it pushes a system to its breaking point in order to find a point of failure.

While a load test measures how a system performs under and expected load, the aim of a stress test is to make the system fail so that overall capacity can be increased. Stress testing is very important in a variety of situations. For example, if you happen to run an e-commerce website and Black Friday is approaching, you may want to conduct a stress test to find out where the breaking point is on your web server and then increase capacity as needed.

Can software be load tested? What software load testing?

Yes—software can absolutely be load tested. When it comes to software load testing, the aim is a little bit different than website load testing.

Because most software is run locally on a machine, its ability to scale to accommodate a larger load is restricted a bit more than a web server that can almost be infinitely scaled to accommodate a larger pool of users. Because of this key difference, software load testing is more focused on ensuring that an increased demand doesn’t result in bugs that crash the software of inhibit its normal functions.

This testing is done through the use of local virtual users, performance counters, and other various tools in order to produce and expected load on software.

What is load testing in terms of software QA?

In terms of software quality assurance, load testing is done to ensure that the software performs properly and meets expectations under varying levels of load.

How is load testing performed on a website?

In order for load testing to be performed on a website, first a load scenario needs to be constructed. This involves determining the amount users that you’d like to have for an expected load situation.

For example, if your company is launching a new product and you estimate that there could be thousands of people visiting the site, then you’d want to account for that in your load planning. Once you know the level of expected load that you need, you can use a load testing tool to create virtual users and have them visit your site with a specific frequency. You may want the users to visit all at once, or alternatively, you may want the users to visit over a more gradated load curve. After you’ve finished conducting your load test, then you need to interpret the results and make decisions about what to do next in terms of improving your capacity.

How does load testing work for websites?

As mentioned above, load testing a website involves creating virtual users and sending them to the site at a specific interval.

This can be done using a variety of cloud servers to simulate virtual users coming visiting your site from all around the world. Alternatively, you can also use load testing software that simulates the users all from a single point of origin. The downside to single point of origin load testing is that because all of the users are coming from the same point (IP, DNS, etc.) you can’t simulate worldwide DNS queries and other more complicated calls that may be barriers to accessing your site under a wide load range.

Ideally, There’s also some type of logging of your data when performing a website load test so that you can go back and see where your problems occurred and why, which can help you with capacity planning.

Can a website be load tested? What is load testing a website?

Yes—a website can absolutely be load tested. The process of load testing a website involves sending a variety of users to a site (either in real browsers or just HTTP requests) in order to produce a specific level of demand to see how the website works.

Load testing a website is the process of applying a specific level of demand to a web server in order to see how the server reacts under those conditions, as mentioned above. Load testing is very useful when it comes to avoiding downtime and other server problems.

Can .NET software be load tested? How do you perform load testing in .NET?

Just like any other software, programs written in ASPX/.NET can easily be load tested. Regardless of the programming language, it’s very important to perform load testing to ensure that you aren’t surprised by downtime or problems created by unexpected levels of user demand.

Performing load testing in .NET is exactly the same as performing load testing in any other type of software as mentioned above.

What is the difference between load and stress testing?

Simply put—load testing involves applying a certain level of demand to see how hardware or software performs under specific levels of load. With load testing, there is typically an expectation of how a site will perform given a specific level of load.

In comparison, stress testing is done to find a failure point. A person performing a stress test isn’t concerned with specific levels of load and how hardware or software performs, but instead is concerned with what level of load is required to produce a failure.

What is load testing with JMeter? What is LoadRunner?

JMeter is load testing software produce the by the Apache foundation. It’s primarily designed to be run on a local machine instead of cloud based load testing which is typically done using a variety of virtual servers.  JMeter is also free software where other types of load testing tools typically require some sort of payment.

LoadRunner is similar to JMeter in that it is available in a free version but it isn’t free software. LoadRunner is produced by Hewlett Packard and is typically used as a paid load testing tool.

Which load testing tool is the best? Which load testing tool should I choose?

There is no single correct answer to this question. If you want to load test software, then you’ll want to find a load testing tool that allows you to do software testing instead of distributed cloud based load testing.

If you want to load test a website, then you’ll want to find a tool that allows you to perform either single point load testing or distributed cloud based load testing. Some load testing tools are free, where others are not and require payment. As with many things, the paid tools are typically more robust and allow for more thorough testing, but that may not be something you need.

What is SoapUI? How is it used for load testing?

SoapUI is an API testing tool created by SmartBear in order to help people test SOAP and REST APIs. It has both a free version and a paid version which comes with more features.

SoapUI is open source and does functional testing which includes message assertion testing and test refactoring. In order to use SoapUI it needs to be downloaded, installed, and configured to work properly with your REST or SOAP API.

Why is load testing done?

Load testing is done to help avoid downtime and failures in both hardware and software. If you can simulate a certain amount of users and ensure that your website, software or hardware doesn’t fail or slow down, then you can be fairly certain that this won’t happen during real world conditions. Simply put—load testing is done to help anticipate, avoid, and correct problems that can occur when hardware of software experiences a specific level of demand.

When is load testing required?

There is never an absolute situation in both hardware and software engineering where load testing is required per se. If can always be foregone, but that means that big problems could exist.

If you want to have hardware that functions properly and software or websites that meet user demands and perform properly, you should always do load testing.

How is load testing with Selenium done?

Selenium is a scripting stool similar to EveryStep and because you can script actions, it’s possible to use it for load testing. However, it’s better to use an actual load testing tool as it wasn’t really created for this purpose.

If you really wanted to do load testing with Selenium, you would just script the user actions over and over again and have the software perform these tasks to simulate load.

How does load testing work?

Load testing works by applying load in the form of demand to websites, web servers, web applications, and other pieces of hardware.

Load testing is usually performed with a variety of load testing tools, depending upon your exact requirements.

What are load testing tools?

Load testing tools are the various hardware and software tools that are used for load testing. Examples of load testing tools include things JMeterSoapUILoadView, and other similar products.

How do you load test an API?

Load testing an API is typically done with an API testing tool such as LoadView or SoapUI.

In order to perform an API test, you need to connect your API to the load testing software and determine the amount of load that you want to apply. Once you know how much load that you want to apply to your API, then you simply configure your API testing software to apply that level of load/demand. After the load test happens, then you would analyze the data and see how your API performed under load according to your expectations.

How do you load test a REST API?

Testing a REST API is similar to testing a standard API but you need to use a load testing tool that is able to accommodate stateless cacheable communications.

There are a variety of commercial REST API testing tools available. The correct tool for you again depends upon your needs.

What’s the difference between load testing vs. performance testing?

Essentially, performance testing is concerned with how fast a system is and load testing is concerned with how much demand a system can handle. While there is some overlap between the two, the main thing to remember is that performance testing deals with issues such as web hosting speed and load testing deals with how your infrastructure handles user demand. If you’re looking to learn more, jump over here for more information.

How do you load test web applications?

Load testing web applications is very similar to load testing a website. However, because web applications require a more complex level of user interaction, load testing them may require more scripting and accounting for other protocols. This means it’s important to find a tool that specializes in testing web applications. Once you have an appropriate tool, the process of applying load and proceeding with the testing is similar to load testing a website. If you’re still looking for more info, check out this list of tools to monitor web applications on

Why do we need load testing?

If we didn’t perform load testing, we would have no idea of how hardware or software would react under certain levels of demand and not knowing these things (and being able to make improvements) could be disastrous.

How does load testing work with WordPress websites?

Load testing WordPress isn’t much different than load testing any other website, with a few exceptions. First, WordPress interfaces with a database, and sometimes under heavy load, communication between the website and the database breaks down, causing slowdowns and other problems. The best way to remedy this is to by choosing a quality WordPress host as many of them have some level of redundancy built in to help with databases being overloaded. The best WordPress hosting companies typically don’t experience a ton of database problems, but it can happen to any host, so make sure to choose wisely (read more here on how to do that).

Do you have to load test a WordPress website’s database separately?

In short, no. While you could use an API to make calls directly to a database, the WordPress software does this for you. Also, if you’re testing a WordPress website, you should be testing the front-end anyway because this is what the users interface with, and this will sufficiently test the database in a real-world setting. If you’re looking for some additional information about how to load test WordPress websites, check out this article – from Web Hosting Buddy to learn more.

How do you do load testing manually?

While load testing can be done manually, it’s typically not something that is done or recommended because of the inability to scale the test. For example, let’s say that you were going to load test a website. You could visit the website in your browser over and over again but your ability to do this rapidly wouldn’t even be close to the ability of automated software to do this and therefore, load testing manually, while possible, is inefficient and ineffective.

Who performs load testing?

Anyone who has an interest in finding out how hardware or software performs under load can perform load testing. This could be a website owner or an engineer for a company—really any with a need for the knowledge that load testing can provide can perform it.

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