How Fast Can a Cloud Run?

August 1, 2010 Off By David
Grazed from New York Times.  Author: Ashlee Vance.

The cloud has been put on notice: It’s being watched.

A new graphical tool from Compuware, CloudSleuth, has arrived, in beta form, to measure and display the speeds at which cloud computing services run. The CloudSleuth tool already tracks, Microsoft, Google and a couple of other cloud providers. And it demonstrates that response times do indeed vary from operator to operator. It displays these results on a map that gives people an idea for the worldwide performance of different data centers at a quick glance.

Imad Mouline, the chief technology officer at Compuware’s Internet monitoring division, Gomez, said he designed the cloud tracking system to provide customers with a way of judging the various services on the market.

“I thought, ‘Why don’t we put these guys to the test?’” he said.

Gomez has set up identical servers in data centers around the globe that request the same files from the various cloud computing systems. It then measures the speed it takes to complete the request.

In addition, Gomez performs similar operations from people’s PCs.

All told, it can build a picture of how the cloud services perform on both high-speed corporate networks and slower home connections.

Looking worldwide over the past 30 days, Microsoft’s relatively new Azure platform has performed the best, responding to requests in 6.46 seconds. OpSource ranks second at 6.61 seconds, followed by Google at 6.77 seconds and 6.82 seconds. (The Amazon figure is for its East Coast data center. Its West Coast, European and Asian data centers had slower response times.)

The rankings were the same for the availability of the cloud systems, leaving Microsoft as the fastest and most reliable cloud provider.

Mr. Mouline stressed that the inner workings of cloud systems are complex because companies have all types of different applications running in the same data center. The interaction of all this software can pose performance challenges and makes the cloud services less responsive than the controlled, fine-tuned data centers that the likes of and Google run for their internal operations.

“Just because you run your application on Amazon’s EC2 or Google’s AppEngine, do not think you will get the same performance as or,” Mr. Mouline said. “That’s the first idea we need to make sure people get away from.

“The cloud is opaque,” Mr. Mouline added. “If you’re running an application in the cloud, you really don’t know what is going on at the infrastructure level.”

The physical location of data centers plays a huge role  in response times. For example, someone in Washington, D.C., requesting a file from’s East Coast data center should receive a response in less than a second, while the same task would take about 11 seconds to complete if the request came from California.

Cloud providers have tended to offer service-level agreements that focused on the overall uptime of their services. says it will be up 99.95 percent of the time, for instance.

But Mr. Mouline urged customers to begin thinking about making response time demands as well.

“We have already seen huge improvements in performance,” Mr. Mouline said. “We know the cloud guys are watching this and trying to improve their scores.”