EBS Volume Types

Amazon Web Services offers diverse Elastic Block Store (EBS) volume types, catering to varied storage and performance needs. These are broadly categorized into SSD volumes, ideal for transactional workloads like databases, and HDD volumes, suited for throughput-intensive tasks like MapReduce. SSD options include General Purpose SSD, Provisioned IOPS SSD for demanding applications, and HDD choices featuring Throughput Optimized and Cold HDD for different access levels. Understanding the specific use cases and performance characteristics of each EBS volume type, from high IOPS SSDs to cost-effective HDDs, is key for optimal AWS storage solutions.

Solid State Drives (SSD)

Solid State Drives are usually preferred in cases where high Input Output per Second (IOPS) is required during a random or sequential I/O operation and are well suited for transactional workloads where the key performance attribute is IOPS.

SSDs in AWS EBS volume types are further classified into General Purpose SSD volumes and Provisioned IOPS SSD volumes.

General Purpose SSD volumes

General purpose SSD volumes provide a high-performance SSD volume at a comparably lower price, hence providing a balance between cost and performance, and are well suited for most workloads, including boot volumes, medium-sized databases, development environments, virtual desktops, etc.

General Purpose SSD volumes in EBS volume types are divided into:

1. gp2: The default EBS volume type for EC2 instances is gp2 volumes, and are highly recommended as boot volumes for EC2 instances. A gp2 volume can range in size from 1 GiB to 16 TiB, while the performance of a gp2 volume scales linearly with its size, larger gp2 volumes have higher baseline performance levels. The below table lists the key performance metrics of a gp2 volume:

2. gp3: The most recent generation of SSD general purpose volumes are referred to as gp3 volumes. At a cheaper cost than gp2, the gp3 volumes provide a constant baseline of 3000 IOPS and 125MB/s throughput regardless of the storage size and additional performance can be provisioned for an additional fee.

The below table lists the key performance metrics of a gp3 volume:

Provisioned IOPS SSD volumes

Provisioned IOPS SSD volumes are the high-performance SSD volumes used for IOPS and throughput-intensive workloads. The current offering includes io1, io2 and io2 Block Express in EBS volume types.

The below table lists the key performance metrics of io1, io2, and io2 Block Express volumes:

For each of the three IOPS SSD EBS volume types, a different amount is paid based on the provisioned IOPS per month.

Hard Disk Drives (HDD)

Hard Disk Drives are usually preferred in cases where high Throughput is required during a large and sequential I/O operation such as reading video files, logs processing, etc. HDDs are cheaper compared to SSDs and ideal for tasks that require high throughput.

HDDs in AWS EBS are further classified into st1 Throughput Optimized HDD volumes and sc1 Cold HDD volumes.

1. st1 Throughput Optimized HDD: st1 volumes provide high throughput for accessing large and sequential data and support frequently accessed storage requirements. Throughput rather than IOPS is the primary performance metric in st1.

2. sc1 Cold HDD: sc1 volumes are the lowest cost volume type and are recommended for less frequent storage access requirements. Throughput rather than IOPS is the primary performance metric in sc1 as well.

The below table lists the key performance metrics of st1 and sc1:

Previous Generation Magnetic Volumes

It is advised to utilize gp2 or gp3 for workloads on AWS, while AWS Magnetic volumes, an earlier generation volume, are still available on the AWS dashboard. Magnetic volumes in EBS volume types offer a volume size of 1Gib-1TiB and maximum IOPS of 40–200. It can be used for infrequently accessed data.