> A single EBS volume allows 10k IOPS max. To get the maximum performance out of an EBS volume, it has to be of a maximum size and attached to an EBS-optimized EC2 instance.
Out of date; EBS volumes can be up to 20k IOPS per volume and what is "maximum size"? To get the maximum performance out of a volume depends on workload, the instance size you've attached it to (rather than EBS Optimization) and the number of IOPS provisioned, and whether you've prewarmed it from a snapshot restore or not.
> A standard block size for an EBS volume is 16kb.
A block can be 1kb -> 256kb in size. It depends on the application.
> EBS volumes have a volume type indicating the physical storage type. The types called “standard” (st1 or sc1) are actually old spinning-platter disks, which deliver only hundreds of IOPS — not what you want unless you’re really trying to cut costs. Modern SSD-based gp2 or io1 are typically the options you want.
The ST1/SC1 wording is misleading. You only need '100s' of IOPS when dealing with big blocks for ST1, and SC1 isn't performance oriented at all.