The Scene of a Crash on the Wild, Wild Web

If you ever wondered what a Web site looks like when it crashes, first look at the donkey photo and then have a look at the chart above. This one pretty much flat lined at 365 users - notice how the red bars (delay) get bigger and bigger and the green bars (bandwidth) get smaller and smaller. The Web Speedometer would be pegged all the way to the right at the end of 5 minutes. (By the way, this chart shows the sign of a server overload, not bandwidth congestion - if that had been the case the green bars would be maxed out while the red bars got bigger and bigger).

This was a Web site of a friend of mine so I had permission to bring it to its knees. It recovered quickly, though, but had I continued for much longer it would have required a system reboot. You might even think of this as a controlled denial of service attack and if so you would be at least partially correct. But if this particular Web site expected more than 300 users they would be spending all their time gazing at the hourglass!

There are lots of good stories about famous web site crashes and I will entertain you with as many as possible here in this blog. One of the most famous of all was when Microsoft first launched their Web site in 1995 - it had been awaited for so long by so many that it immediately crashed upon startup! After doubling or tripling the number of servers it came up again and crashed in two days! I can't remember how many times it took them to get it right but you can only imagine the size of their data centers nowadays.

A service that CapCal is now offering is called CloudBurst, and it's basically the ability to do what I did to my friend's web site to find out exactly the point where capacity and performance are no longer sufficient. That could be millions of users in some cases and nobody has ever done a million user load test, or even half a million. I would love it if someone could prove me wrong but I know how many computers it would take and I doubt anyone has that many machines sitting around doing nothing - not physical machines anyway!

I'm hoping (with Amazon's help) to break the 1 million user barrier someday and with CapCal's ultralight agent that can be done with just a few hundred instances. I'll be posting on a regular basis about CapCal CloudBurst and its race for a spot in the Guinness Book of World Records so please check back frequently!

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