Load Testing is the process of putting demand on computer devices to analyze the performance of the device under extreme conditions. Usually, the load test is carried out to gauge the response under normal conditions; however, testers also use load test to measure the extreme load that a device is able to handle. During the test, the system evaluates the operating capacity of the computing device to check for potential errors and bottlenecks. There is a variety of load testing software programs available in the market, which are primarily used to determine the slow performance. Accordingly, the slow performance can be attributed to malfunctioning application server, database server, networking or client-side processing.
Difference between Load Test and Stress Test
In the computer industry, there is usually a difference between load testing and stress testing. Basically, a load test is used to test the response of a device under normal conditions. In contrast, stress testing is used to test the device under extreme conditions, which may give error results, mostly. Since there is no pre-defined limit on what constitutes load test and stress test, it is useful to understand that stress testing can also be conducted to determine an extreme load under which an operating device will behave normally.
After optimal performance parameters are determined using load test, technical experts often put additional load on the application to test its functions under adverse conditions or during times of high traffic. Such tests, carried out to check the feasibility of an application beyond its normal usage, are often termed as stress test because the system is hypothetically under a lot of stress.
How the Load Test is Conducted?
In the software performance industry, the load test refers to the normal operating procedures when multiple users use an application. For the purpose, a testing facility may conduct several load test before approving the application for public use. Hence, various live users and virtual users may be used to test the application. While one type of load test may evaluate number of virtual users and live users using an online shopping cart, another load test may test how the shopping cart behaves when these users add and delete multiple items simultaneously in a quick succession. The load test can also vary according to the number of users involved. In addition, the test can also involve testing the system using different configurations.
Alternative testing resources:
When a new software application is developed or an existing application is improved upon, before it is released for public consumption the originator of the application runs it through a series of vigorous test procedures which answer three distinct sets of questions. Does the application perform as well as was intended and will be marketed; are there any potential flaws that will cause instability and system interruptions during the operation of the application; and what are the limitations of the application? Each of these questions is answered through the performance of specific tests which are referred to as performance, load and stress testing respectively.
In performance testing there are two fundamental goals which are to test the connection speed of the application and its latency or the difference between the time data travel from its source to its destination. Depending on the application, testing its performance can be quite simple or rather complex.
Load testing has an entirely different set of goals which are mainly targeted at exposing defects in the application so that they can be corrected. Problems discovered in load type testing typically related how the application manages its available recourses. Memory management or rather mismanagement and buffer overflow are common issues that are discovered when this type of testing is performed.
Utilizing scripts specifically written to simulate one or a number of users simultaneously performing the various task the application was intended to perform, problem areas are rooted out as the load on the system is increased. As corrections are made to remedy weaknesses discovered in the application, this process is repeated until the application can endure a load on the system that meets or exceeds the desired results and provide consistent results.
Also, one important thing to understand about load testing is that if you have a poor quality web host, you’re going to have poor quality results in general when it comes to the speed of website. Not all hosts are created equally, and this is important to understand. Shared hosts will typically not do as well in a load test as a VPS or dedicated setup. For example, when comparing hosts, such as Bluehost vs HostGator, you would typically expect their shared offerings not to perform as well as their VPS or dedicated server offerings, etc. With that said, let’s jump back to looking at load testing vs stress testing.
Last there is stress testing. While there may appear to be some similarities to load testing, stressing the system servers a very different and arguably a more critical purpose. The goal is simple, overload the system until it crashes and see how it recovers! A great deal can be learned from stressing the system but most important is to understand is if in the process of crashing, whether or not the security of sensitive data is compromised. Every web server has the ability to be pushed beyond the systems limitation, it is how smoothly it is able to recover and that it does so without data compromise which is important.
A consumer asked, “How much do I owe for your services?” the computer tech replied, “$50.00 Ma’am.” The consumer started to write down what she was to pay for, and upon reaching the end of a lengthy list, said, “So, $50.00 for the load testing…”, “Ye’”, the computer tech started to respond but was cut off, “…$50.00 for the stress test, $50.00 for the software performance test, $50.00 for the reliability test, and $50.00 for the volume test. Do you have a payment plan? I really wasn’t prepared to pay a $300.00 fee to see if the computers in my office could work on graphics, word processing and my financial reports at the time time.”
The computer tech was stumped, and so it goes. Yet, in all of her confusion, she summed up exactly what load testing tells us – in essence, how software being used on multiple computers within a network will function if they are working at maximum capacity. Our software company has expanded over the last year to better accommodate the consumers we serve and to help our bottom line. Growth can be painful, so we have created a simple information section on our website that explains many basic processes so that our techs can clearly share what they are doing. It is also helpful for our consumers because they can read over the information that breaks everything down for them.
We started with load testing. Load testing, aka concurrency testing, aka software performance testing, aka reliability testing, aka volume testing (there goes the $250.00 bonus our consumer was about to give our example tech), is a way to check a system’s performance when everything is normal vs. when it is at a peak performance load. There is not a clear point that delineates when a load test becomes a stress test. How the system handles high loads is generally called a stress test, but the terms are used interchangeably, in some cases.
It gives us information about how a system deals with many users, at the same time. Load testing is about mimicking real use rather than an analytical test and can help consumers learn about why their system is slow due to things like application software/application servers, network congestion, network latency, database servers, processing (consumer) and multiple servers’ ability to balance the load between them, with no playback capabilities.
Technology is not unbreakable, many programs have their breaking point at which they no longer will work to their full capacity. It is important to determine the capability of any new program before it goes to market by either testing it using load testing or stress testing. These sorts of tests can be compared to software performance testing because that is basically what they are doing.
Load & performance testing and stress testing both deliberately overload a program or system to test its breaking point. They also test the program in normal conditions to show how it should be working when all variables are normal. It is important when it comes testing a program that it gets tested in two different fashions: endurance and longevity. Not only does a programmer want their program to work quickly, but they want their program to have a long existence of service. Most software programs cost a great deal of money to actually reach a workable capacity, so throwing in a load or stress testing at the end of its programming is vital to its success.
Some of the main elements stress testing and load testing test for include:
Downloads of large files from the internet
- Number of downloads that can be done at a time
- Assigning multiple jobs to a printer queue
- Writing hard disk data
- E-mail and the internet traffic
- Running multiple applications at once
Load and stress testing can be done in multiple different ways. They offer programs that help test out your software or website to prove its performance rate. If the software program being created is being programmed by a high volume software development team, there may already be a person on site who is able to put a stress or load test on the software.
Depending on the software program that is being tested, there are different variables in which load testing test for, it is a beneficial way to prove a system capable and performance. It also lets programmers know if their system needs some fine tweaking before it can go to market. It is important for all new software programs to be subjected to some sort of load or stress testing because if not, a system may not be capable of handling the capacity load and could crash.