I was wondering why the text read a great deal like a VNR (video new release).<p>The analysis may be "independent", but the fine print at the bottom of the article indicates that it was paid for by Rackspace.
Compiling the linux kernel seems like a poor choice of test, since it is not a pure CPU activity and will perform a significant amount of I/O.<p>In addition, it doesn't seem like compiling the linux kernel requires very much RAM, so you get the most bang for your buck using a CS VM with only 256MB and the cost only goes up from there as you add more RAM that the test cannot benefit from.<p>(Edit: I would love whoever downmodded me to explain why I am wrong.)
Crank curmudgeon review: Loses big points for including illegibly down-filtered graphs in the page. Either make them readable or make them links. Using fancy animations isn't an excuse for including 600x266 pixel unreadable blotches in your document.
In my own informal experience, running identical CPU-bound tasks on Rackspace and EC2, it's just a lot easier to get good performance on Rackspace.<p>Instance size on Rackspace does affect performance (as their FAQ explains), but it affects minimum guaranteed performance; there's bursting up to the capacity of the entire machine you have a slice of. I know there's something unsettling about relying on excess capacity, but in practice any Rackspace instance will tend to beat any but the most expensive EC2 instance in terms of raw CPU.<p>The sweet spot of EC2 really is offline processing where hundreds or thousands of machines are spun up by software. If you want to manually fire up a small but flexible number of fast Linux machines, I would recommend Rackspace.
Who makes a living compiling a Linux kernel? Perhaps web comparison benchmarks weren't selected because they weren't favorable to Rackspace?<p>Do they feel their cloud offerings are inferior to Amazon's?
This is probably a little better comparison of CPU performance between the difference platforms and a couple others: <a href="http://journal.uggedal.com/vps-performance-comparison" rel="nofollow">http://journal.uggedal.com/vps-performance-comparison</a>
It's nice to see an analysis that looks at more than just CPU. Disk I/O can be very important in some cases.<p>It's also nice to see the tests being done over a period of time, rather than a single day.