Choosing the right EBS volume type

• SSD-backed volumes, such as General Purpose SSD (gp2) and Provisioned IOPS SSD (io1):

  • Small and random I/O operations.

• HDD-backed volumes like Throughput Optimized HDD (st1) and Cold HDD (sc1):

  • Large and sequential I/O operations.

• Unlike gp2, which uses a bucket and credit model to calculate performance, an io1 volume allows you to specify a consistent IOPS rate when you create the volume, and EBS delivers within 10 percent of the provisioned IOPS performance 99.9 percent of the time over a given year.

• Provisioned IOPS SSD volumes are much more suitable to meet the needs of I/O-intensive database workloads such as MongoDB, Oracle, MySQL, and many others.

• Throughput Optimized HDD (st1) and Cold HDD (sc1) are more suitable for workloads with large, sequential I/O operations instead of small, random I/O operations.