All of AWS, really. My experiences with EC2 were abysmal: unpredictable CPU and disk performance, uselessly slow disk I/O, instances dropping off the face of the earth at least once a week.

Reddit's recent downtime is a good indicator of how sloppy AWS as a whole really is.

I agree with slow disk I/O, but how do you think Netflix is doing so well with EC2? Adding more machines than they need to?

They put in great engineering effort to ensure high availability despite random instance failures. I really like their Chaos Monkey.

See: http://techblog.netflix.com/2010/12/5-lessons-weve-learned-u...

It's cool that Netflix pulled that off, but it seems like a company (like Dotcloud) that could prevent you from building infrastructure on top of infrastructure would be a boon.

One could argue this is how all systems should be designed anyway.

As a high-profile EC2 client, I imagine Amazon gives Netflix tons of "complementary" support. A Netflix failure on EC2 would be a big black eye to Amazon PR.

the outages@outages.org mailing list says that Netflix was down today. I don't know if it's ec2 related or not... I was actually hoping someone might have details.

https://puck.nether.net/pipermail/outages/2011-March/002786....