Revenues are growing 50% to 70% year over year, Finsterwald says, so Karmaloop is using Keynote's LoadPro Web load-testing services to ensure its site is not strained. Because its CDN network was not optimized to handle this level of traffic in past years, the site experienced "frequent" network outrages, he said, although he declined to provide specifics.
"It gives you peace of mind that we can come up with a reasonable facsimile under peak load,'' Finsterwald says. "Load testing is an inelegant science; you're trying to simulate user traffic, but you're integrating a lot of third-party components." If a test is done on a quiet day, a third party may be able to scale to handle that, but all bets might be off when they're handling multiple clients.
This year, when conducting load testing, Karmaloop scaled its systems to a high enough load to trigger a problem for the vendors to address proactively. "We saw performance degradation with some of our vendors," says Finsterwald, "so we're following up with them to make sure they're doing what they need to do."
Keynote's Karow concurs. "Load testing done right has to be a very close representation of what real users are going to do, so it takes real thinking about what people do and the various systems involved and are you stressing those systems?"
Talk to your stakeholders
Also critical to the success of keeping systems up and highly available is making sure everyone is on the same page. "Everybody needs to be involved in the planning and predictive process,'' says Zappos' Ongbongan. At Zappos, that means everyone from brand marketing to financial planning to warehouse staff is involved in planning for peaks in site traffic.
One thing his group learned from talking with other departments was that their peak traffic typically occurs in mid-December, as opposed to right after Thanksgiving or right before Christmas.
Forrester's Gualtieri says it's a definitely a problem when a marketing group doesn't let IT know what it's doing that might cause site traffic to spike. He says he worked with a large Midwestern insurance company that spent a couple of million dollars on its first TV ad during a football game. When the ad aired, the company's site went down "almost instantly," because the company's marketing department didn't tell IT it was running the ad. "So IT had no idea they were going to expect 500 times the normal amount of traffic,'' he says, and they ended up wasting their money on the ad.
Despite all the proactive measures retailers may be taking, Gaultieri predicts there will still be "some high-profile outages" this holiday season. "One, two or several will happen. I also think a lot will happen that you'll never hear about ... I don't think this problem is going to go away."
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