7. Configuring Storage for Vector on AWS : Tuning Volume Layout for Performance : EBS Volumes
 
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EBS Volumes
EBS volumes are similar to instance stores but offer multiple options for HDD and SSD types. In addition, performance limits are tied to each type, and there is a maximum performance for each volume type that is related to the EC2 instance type.
A good overview of the various EBS options is available at https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSVolumeTypes.html. Detailed limits for volumes based on instance type are at https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSOptimized.html.
After you add the EBS volumes to your instance (something you can do at launch time or while the instance is running), you must format them and make them available before they can be used (see https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-using-volumes.html).
We have found that st1 volumes generally offer a good performance/cost tradeoff.
Note:  There are limits to performance per volume. For example, a single st1 volume of size 2 TiB can deliver a maximum burst performance of 500 MiB/second. However, the EC2 instance itself can cap EBS performance (see https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSOptimized.html). For example, if you use a 2-TiB st1 volume on an m4.4xlarge instance, you will get only 250 MiB/second since the EC2 EBS performance overrides the EBS volume performance. However, if you choose an m4.10xlarge EC2 instance, you will get the full burst performance of 500 MiB/second from EBS since an m4.10xlarge has a cap of 500 MiB/second for EBS throughput. If you choose to go for a larger instance, for example, an m4.16xlarge, which has an EBS maximum throughput of 1250 MiB/second and would like to be able to achieve that throughput, you could use 3 x 2 TiB EBS volumes for this instance in a RAID configuration (see https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/raid-config.html), which theoretically would give you a 1500 MiB/second (3 x 500) burst throughout, and the EC2 cap effectively would result in 1250 MiB/second.