The ongoing cost for running Datomic EC2 instances can be reduced by purchasing AWS Reserved Instances (RIs).
Once you have established your system topology you can purchase Reserved Instances for the EC2 instances types used in your system. AWS will automatically apply the purchased RI discount to your infrastructure (EC2) cost for any instances matching the purchased RI attributes.
Determining Instance Sizes
Standard RIs are purchased for a specific EC2 instance type. You can determine the type(s) and quantities of EC2 instances your Datomic system uses by searching for the keyword 'datomic' in your EC2 Console:
Note the instance type(s) and number of instances running in your system. You can purchase RIs for any or all of the Datomic system instances.
Purchasing Reserved Instances
Browse to the 'Reserved Instances' section of the EC2 Console and click the "Purchase Reserved Instances" button:
In the popup dialog, enter your desired RI search parameters and click the "Search" button. This example demonstrates searching for RIs for a default Solo topology stack (1 t3.small instance) for a 12 month term:
Generally, options with higher upfront costs provide greater hourly discounts.
RIs will be automatically applied to running instance(s) matching the purchased RI attributes.
Additional options for purchasing and applying RIs can be found in the Reserved Instances Guide.