Choosing AWS Eon Mode Instance Types

This topic lists the recommended instance types to use in an Eon Mode database running in AWS.

Choose instance types that support ephemeral instance storage or EBS volumes for your depot, depending on cost and availability. It is not mandatory to have an EBS-backed depot, because in Eon Mode, a copy of the data is safely stored in communal storage. Vertica recommends either r4 or i3 instances for production clusters.

The following table provides information to help you make a decision on how to pick instances with ephemeral instance storage or EBS only storage. Check with AWS for the latest cost per hour.

Storage Type Instance Type Pros/Cons
Instance storage i3.8xlarge

Instance storage offers better performance than EBS attached storage through multiple EBS volumes. Instance storage can be striped (RAIDed) together to increase throughput and load balance I/O.

Data stored in instance-store volumes is not persistent through instance stops, terminations, or hardware failures.

EBS-only storage

r4.8xlarge with 600 GB

EBS volume attached

Newer instance types from AWS have only the EBS option. In most AWS regions, it's easier to provision a large number of instances.

You can terminate an instance but leave the EBS volume around for faster revive. Perserving the EBS will preserve the depot. While some of the cached files might have become stale, they will be ignored and evicted. Much of the cached data will not be stale. It will save time when the node revives and warms its depot.

Take advantage of full-volume encryption.

If you select instances that use instance store, if you then terminate those instances there is the potential for data loss. For Eon mode, MC displays an alert to inform the user of the potential data loss when terminating instances that support instance store.