Managers of leading ecommerce sites were told they need to re-examine their handling of peak traffic periods, after disappointing users at peak online Christmas shopping times.
Round the clock independent tests, performed every hour by eight automated agents located across the UK and Eire, show that leading ecommerce websites such as ToysRus have taken up to 62 seconds to load during peak lunch hour periods.
"These figures are shocking; they are totally unacceptable," said Oliver Carron, vice president, Europe, Middle East and Africa, at Keynote Systems, which has been examining 20 leading UK online retailers since the start of the month.
He told vnunet.com: "Some websites have clearly doubted whether they will be successful and haven't prepared for the level of traffic they've achieved.
"Research by [market watcher] Zona has shown that, in ecommerce, there are so many alternatives for shoppers that any download speed of more than eight seconds is disastrous."
As well as ToysRus, fellow toy shop Hamley's recorded times as high as 49.67 seconds and Sainsburys.co.uk, a non-ecommerce website, slowed to 44-46 seconds on occasions, but the company insisted that its new sainsburystoyou.com ecommerce site performed better.
"We completely dispute the findings," a spokesman for Sainsbury's said. "Since our relaunch in October, orders have increased by 30 per cent."
Overall, Carron said that the standard was improving. "The majority now take under four seconds to load. All ecommerce providers should aim for a similar, sustained performance," he explained.
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