[vegardx]

Seems like you were using T2 instances which have a low baseline performance and burst credits. I would imagine that you quickly run out of credits on some of the smaller instance types after creation, given how lengthy and costly (in terms of CPU usage) the instance creation and boot process is.

[Zombiethrowaway]

I was typically using c3.xlarge for CPU-intensive tasks (video processing).

Boot time was OK. I would log in on the machine with RDP, because sometimes my processes were almost frozen for a while. It felt like my neighbours were stealing my CPU, but I did not know how to prove it.

Once I moved to Ubuntu, same instance type, I never experienced this.