While some of us were riffling through empty pocketbooks or puzzling over the latest generation of exercise technology in our newly joined gyms in January, a goodly proportion of Europeans were thinking much further ahead. They hit online travel sites to book vacations ... and if those sites froze or let them down, they just clicked to a rival and valuable winter sales could be lost forever.

"British people tend to book their midyear holidays as soon as the year starts, basically," said Andy Dean, service delivery manager, U.K. and France, for Thomas Cook Online, the e-commerce arm of the $14 billion (£9 billion) group.

The Thomas Cook online travel agency is made up of about a dozen websites that serve clients worldwide, with the U.K. version its largest. It also brings in 40% of its entire U.K. business (the firm also has retail stores in the country, though not in the rest of Europe); so if a transaction messes up, especially at peak booking time, then that prospect just might never come back.

[ Want to guard your site against lost business from frustrated e-commerce users? See Why Application Performance Management Matters Now. ]

That's a danger underlined by just how keen Brits are on booking their "summer hols" online in the depths of the cheerless British winter. Deloitte data cited by the European Travel Commission showed 86% of overseas and 91% of domestic travel transactions in the country are now "digitally influenced." That means, even if the final purchase isn't made online, about nine in 10 travel purchases are influenced by things like websites, social media, peer reviews and smartphone or tablet apps. The same source quotes Google to the effect that 80% of travel products in the U.K. are researched or purchased online -- the highest figures for any country in the world.

Dean says that end-user Web application performance monitoring using Dell's Foglight has decreased the prospect of commercial nightmares at his London-headquartered organization, which claims 23 million customers and which has more than 30,000 staff. "We were really struggling without real-time visibility of real visitor experience," he told InformationWeek. "That was costing us revenue."

In fact, he said, Foglight, part of Dell's $2.4 billion acquisition of Quest Software in 2012, has actually boosted sales by 30%, equaling $426,000 (£274,000) per hour.

Let's put all this in a bit of context. The Thomas Cook site typically receives about a million hits per day. But that can triple during that peak January - February period. Dean says poor site performance was costing it too many potential sales in what should have been the most lucrative sales period. A year on from implementation, the team reports it's making an additional 180 bookings per hour compared to previous results at that time of the year. Dean is also happy to report that the time to find and resolve a problem has dropped 97% (from 48 hours to one to two hours), calls to customer service by frustrated wannabe-holiday bookers have decreased from 35% of online users to 15%, and real-time alerts (triggered if bookings drop below a specified threshold or page load is deemed unacceptably slow) have sharply dropped.

"Having real-time data and insights on what the user actually saw on their screen when things went wrong has been a big help to us," Dean said. He has also customized the package to recapture lost business by automatically emailing colleagues in the customer retention teams with details about non-bookers so they can follow up and offer points of contact to try and win their orders, even after a possibly disappointing online experience. The company said use of the monitoring tool has already enabled the recapturing of an estimated $190,000 of business over three months via that program.

Prior to deploying the Dell software, Thomas Cook had a website monitoring system, but it wasn't much use. It was unable to help identify and resolve performance issues and only provided limited visibility into a site user's actual experience, making it difficult to gauge the impact of problems and understand why a person abandoned the site. As Dean put it, "Previously, we would have learned of an issue at the end of the day, and it would have taken hours to identify the problem." Another benefit: he was able to identify a nagging problem with an application server he said he wouldn't have been able to spot otherwise.

Seems like a bit of fine tuning has delivered big benefits for this busy e-commerce site -- and helped bring a promise of Vitamin D to shivering, damp Brits over the post-holidays period.

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