To test web applications, synthetic web performance monitoring scripts and tests what users might do on a site. Real-user monitoring, a recent development, skips the script to capture actual user sessions.
To test the speed and availability of web site applications, site operators have used synthetic performance monitoring: scripted test scenarios that seek to replicate user sessions. But as sites become more complex and more heavily-traveled, second-guessing what users might do and how it could drive applications awry gets more unwieldy. By deploying real-time monitoring of actual user interactions with site applications on a 24/7 basis, performance monitoring provider Coradiant Inc. says it`s been able to cut time and resources needed to resolve application performance errors by 20% and error rates by 50% at client sites.
VP of marketing Tom Clarkson says synthetic monitoring excels at testing a site’s speed and availability from different locations, but that when monitoring for application errors, synthetic testing captures only the scenarios the tester has scripted tests for. A large site with many products, many ways to come into the shopping cart and many ways of presenting information to shoppers, for example, would require a script to monitor for each combination.
“Part of the problem with synthetic scripts is that they only test your idea of what a user might do,” he says. “Real users do very unanticipated things on a site.” As a result, non-scripted – and therefore not tested-for – errors go undetected by synthetic testing, he says. Testing for application errors synthetically also captures only slices of time. “If you are set to test every 30 minutes, a lot can happen in between that synthetic testing is blind to,” Clarkson says.
Real-user monitoring systems such as Coradiant`s product, TrueSight, which launched last November, have emerged relatively recently. The underlying technology is something new. It’s a hardware appliance, installed at the network level at a company’s data center, which “sees” all network traffic, logs all user sessions, and reports out on them. Being able to pinpoint where and in which sessions errors occur has been the key driver in cutting error resolution time among companies using the product, Clarkson says. And that’s been responsible for cutting error rates by as much as 50% at some client sites by allowing site operators to find and fix application errors before they are exposed to additional site visitors, he adds.
Clarkson makes the point that unlike web analytics packages that seek to track customer behavior across a web site, real-user performance monitoring`s goal is to capture sessions and not the path of an individual from session to session. About 25% of Coradiant’s customer base is conventional retail, including Proflowers.com and MLB.com, he adds.