Scripting a load test can be a great example of the Pareto Principle in play. Configuring a load test is difficult. There are tons of parameters you can tweak in order to achieve the kind of user behavior and simulation you want. Many people approach load testing with the ambition to simulate reality perfectly in their load test, so they'll learn exactly how many real users their production system will be able to handle. Unfortunately, simulating reality is difficult, which means it takes a lot of time and effort to set up such a test, and many times even a major effort will fall short and miss some critical aspect that causes the simulation to be unrealistic.
Organizations that spend tons of time and money on a load test are not likely to do any load testing except when it's necessary.
Often, this will be just before a launch, when there's little time to fix any problems found and the cost of fixing them will be high because the problems are found at such a late stage.
Here's where the Pareto Principle enters the scene: if you don't try to simulate reality perfectly, your configuration will be a lot simpler. You can get away with spending only 20 percent of the effort of setting up the load test. The result you get might not be a number telling you exactly how many users your site could handle in production, but it's likely to tell you if your performance is way off target , and it'll likely highlight your performance bottlenecks.
Because the test is much simpler to configure and run, you can run more tests at various stages of development and learn a lot more in aggregate than you would've learned from a single test. Being able to run more tests earlier on makes it possible to detect and fix performance issues earlier, and fixing an issue as early as possible usually means saving development time, which drives down total project cost.
More frequent testing will also result in a team that is generally more confident and more involved in product performance. Exactly where to cut away complexity in your load testing will depend on your situation, but it could mean that you might want to use a simplistic version of user behavior when designing your load test.
The simulated user in your test might be a lot more static in its behavior than a real user, perhaps just accessing a set sequence of pages or content with no randomization. Or you may have your simulated users access a randomly selected page on your site, choosing to ignore the fact that some pages are much more heavily visited than others. If you're testing an API-driven application like a mobile app , you might find it better not to care about user flows and instead try to exercise API endpoints—either as a mix or perhaps even individually.
If you know how many calls per second API endpoint "X" will have at 1, concurrent users, you can run a load test that generates that number of requests per second and see if your back end can handle it and where in your system the bottlenecks appear. Then do the same thing for each endpoint you can of course exercise multiple endpoints in the same test if you want.
Stress tests also look for memory leaks, slowdowns, security issues, and data corruption. Stress testing can be conducted through load testing tools by defining a test case with a very high number of concurrent virtual users.
Just as a stress test is a type of performance test, there are types of load tests as well. If your stress test includes a sudden, high ramp-up in the number of virtual users, it is called a Spike Test. We presume the system will be under traffic three minutes into the test.
Run stress tests against your website or app before major events, like Black Friday , ticket selling for a popular concert with high demand, or elections. Utilize all the types of performance tests detailed here to ensure you are always aware of any issues and can have a plan for dealing with them. JMeter can be enhanced through BlazeMeter, which provides larger scalability, many geo-locations around the world, better reporting and sharing capabilities, multiple integrations, and recording options.
Request a demo to learn more. To try BlazeMeter out, set up a free account, put your URL in the box below, and then your test will start in minutes. This blog post was originally published in and was updated for accuracy in December Interested in writing for our Blog? Send us a pitch! Previous API Testing. Authentication Testing. Best Practices. Black Friday. Continuous Integration. GUI Testing. JMeter vs LoadRunner.
Live Streaming. Load Testing. Mainframe Testing. This could quickly identify infected people, even if the assays are less sensitive than a PCR-based test, because the amount of virus in their noses and throats rises within hours, he says. Mina and his colleagues have used statistical models to assess this strategy. In a preprint updated on 8 September, they suggest that testing people twice a week with a relatively insensitive test could be more effective at curbing the spread of SARS-CoV-2 than are more-accurate tests done once every two weeks 1.
Another study that modelled different scenarios for safely reopening university campuses reported similar findings 4. To slow outbreaks, the focus should be on identifying those who are at risk of spreading SARS-CoV-2 to other people, rather than on spotting anyone who is infected with it, some experts say.
At the beginning of April, as coronavirus outbreaks raged across the world, India had tested only about , people — one of the lowest testing rates per capita worldwide. On 21 August, the country conducted more than one million coronavirus tests in a single day.
It reached that milestone after Indian authorities began using antigen assays to boost testing capacity. Scientists baffled by decision to stop a pioneering coronavirus testing project. Delhi was the first Indian state to begin using rapid antigen tests, in June. By mid-July, the number of cases there had decreased and the daily death counts had plateaued, suggesting that the tests might have played some part in controlling the spread of the virus.
Epidemiologist K. Srinath Reddy, president of the Public Health Foundation of India, a non-profit organization in New Delhi, says that the Delhi example is interesting, but not clear-cut: he notes that the government started to lift lockdown restrictions in August, which led to a surge in infections. So far, India has approved the use of three antigen tests for screening large numbers of people, whether or not they have symptoms.
Guidance from the ICMR says that people who have a negative result from an antigen test should also get a PCR test if they show symptoms, to rule out the possibility that the rapid test missed an infection. The US FDA has so far granted emergency use authorization for four antigen tests, each of which has a higher sensitivity than those used in India.
The FDA, however, has authorized antigen-based tests only for people who have had symptoms for 12 days or fewer. Tests must be prescribed by a physician and administered by a health-care professional.
A testing centre at the international airport in Rome. Italy plans to use rapid antigen tests to screen passengers at all of its airports. Other countries are also considering the use of rapid antigen tests to meet targets. In July, the Philippine Society for Microbiology and Infectious Diseases issued temporary guidelines for clinicians and health-care workers, saying that antigen tests could be used as an alternative to PCR for diagnosing a coronavirus infection during the first week in people with symptoms.
Negative results do not have to be confirmed with a PCR test. When trying to contain small outbreaks, such as those happening in Italy, public-health authorities should use assays that are highly accurate, because missing even just one positive individual could lead to a steep increase in the total number of cases, says Andrea Crisanti, a microbiologist at the University of Padua. Several experts have promoted the idea of developing an antigen test that is cheap and simple enough to use at home, without a health-care worker administering it.
The sprint to solve coronavirus protein structures — and disarm them with drugs. A few companies are developing simple paper-strip antigen tests. But drug regulators have not yet approved them for emergency use. Without incentives such as freely available tests and a living salary for those who have to isolate, testing and self-isolation could become a luxury reserved for wealthier people, others have argued.
Another concern is that people will get a false sense of security from tests that have only limited accuracy. Even when testing negative, people should continue to wash their hands, wear masks and avoid gathering in big groups, she says.
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