Usage Patterns - AWS Storage Services Overview

Usage Patterns

In general, EC2 local instance store volumes are ideal for temporary storage of information that is continually changing, such as buffers, caches, scratch data, and other temporary content, or for data that is replicated across a fleet of instances, such as a load-balanced pool of web servers. EC2 instance storage is well-suited for this purpose. It consists of the virtual machine’s boot device (for instance store AMIs only), plus one or more additional volumes that are dedicated to the EC2 instance (for both Amazon EBS AMIs and instance store AMIs). This storage can only be used from a single EC2 instance during that instance's lifetime. Note that, unlike EBS volumes, instance store volumes cannot be detached or attached to another instance.

For high I/O and high storage, use EC2 instance storage targeted to these use cases. High I/O instances (the i2 family) provide instance store volumes backed by SSD and are ideally suited for many high-performance database workloads. Example applications include NoSQL databases like Cassandra and MongoDB, clustered databases, and online transaction processing (OLTP) systems. High storage instances (the d2 family) support much higher storage density per EC2 instance and are ideally suited for applications that benefit from high sequential I/O performance across very large datasets. Example applications include data warehouses, Hadoop/MapReduce storage nodes, and parallel file systems.

Note that applications using instance storage for persistent data generally provide data durability through replication, or by periodically copying data to durable storage.

EC2 instance store volumes don’t suit all storage situations. The following table presents some storage needs for which you should consider other AWS storage options.

Storage Need Solution AWS Services
Persistent storage If you need persistent virtual disk storage similar to a physical disk drive for files or other data that must persist longer than the lifetime of a single EC2 instance, EBS volumes, Amazon EFS file systems, or Amazon S3 are more appropriate.

Amazon EC2 Amazon EBS

Amazon EFS Amazon S3

Relational database storage In most cases, relational databases require storage that persists beyond the lifetime of a single EC2 instance, making EBS volumes the natural choice. Amazon EC2 Amazon EBS
Shared storage Instance store volumes are dedicated to a single EC2 instance and can’t be shared with other systems or users. If you need storage that can be detached from one instance and attached to a different instance, or if you need the ability to share data easily, Amazon EFS, Amazon S3, or Amazon EBS are better choices. Amazon EFS Amazon S3 Amazon EBS
Snapshots If you need the convenience, long-term durability, availability, and the ability to share point-in-time disk snapshots, EBS volumes are a better choice. Amazon EBS