I just took a couple of these for a quick spin so that I could have an answer if anybody asks about them tomorrow (I'm doing a LISA'13 talk about cloud storage performance). They really are pretty zippy. Basically they seem about 3x as fast as their predecessors, particularly with respect to disk I/O. The 1GB type is among the fastest in that category at over 15K (synchronous random 4KB) IOPS, for only 50% more per month than competitors. The 15GB type got over 28K IOPS, which is among the best I've seen in a public cloud (e.g. Storm on Demand 12GB or the astronomically priced AWS hi1.4xlarge).<p>Network-wise, I got the usual Rackspace throttling-induced asymmetry - 194Mb/s going from the 1GB instance to the 15GB, 874Mb/s the other way. Likewise, the cloud block storage significantly underperformed the instance storage at just under 8K IOPS - though that's still really nothing to sneeze at in a public cloud.<p>For something you can rent by the hour these are pretty sweet. It's not too hard to find 10KIOPS-capable machines elsewhere for much less, but then again those IOPS might not do you much good if the machines are network-constrained (and many of the cheaper providers do tend to be). As always, measure for yourself. It's always good to see that bar being raised.
The email announcing it it was rather vague. "A note from Lanham, Rackspace CEO, on a new definition and focus on performance."<p>It goes on to note how performance is important and invites clients to "contact a Racker to talk about your performance objectives.". The words "server" and "SSD" don't even appear in it. Well, at least he didn't invite us to "dialogue".<p>But anyway, seems to be all SSD now, but no longer resizable machines. Some more technical notes here: <a href="http://www.rackspace.com/knowledge_center/article/what-is-new-with-performance-cloud-servers" rel="nofollow">http://www.rackspace.com/knowledge_center/article/what-is-ne...</a>