The French-based company Cedexis has come up with a Cloud Performance Index. It's an interesting way to measure the performance of your content delivery network or cloud-based provider, and a useful way to determine which provider you should use - or even which part of the planet you should locate your apps. Every day on its website, Cedexis will publish new country-by-country performance reports on various IT providers. The info is collected via a Javascript tag on its customers' sites. The tag is counted only if the entire page has loaded.

For example, above is a report on the various French Internet providers. As you can see, the most measurements are collected from Orange and Proxad. The fastest page load times are 4.1 seconds from Adista, and the slowest are 6.5 seconds from Mobius.

The range of variation for U.S. ISPs is from 3.9 seconds from Cablevision to 5.4 seconds from Cogent. If we were to look at U.S.-based cloud providers, the fastest response times are from VOxCloud in Amsterdam and New York, faster than Amazon EC2 even, as you can see from the partial graph below.

Cedexis, which is trying to push its agenda of having customers use multiple cloud providers to deliver apps, presents three different data sets: one for general ISPs, one for content networks and one for cloud providers. In addition to average response time, there is also a statistic on the percentage of times that a page timed out or resulted in other errors. For example, in the U.S., Google's App Engine had the highest error rate of 2.6 percent.

There are other companies that provide similar data, including CloudSleuth, which we wrote about last fall. CloudSleuth takes a moving average over the past 12 months' worth of data, rather than the daily stats that Cedexis uses, so the data isn't directly comparable. Still, for choosing the right ISP or cloud provider, it is an interesting first place to look.