Amazon offers two distinct services with similar names - Amazon ElastiCache and Amazon Elasticsearch (now known as Amazon OpenSearch Service). These two services serve entirely different purposes but both have their own pricing strategies.
Amazon ElastiCache is a web service that makes it easy to set up, manage, and scale a distributed in-memory cache environment in the cloud. It improves the performance of web applications by retrieving data from fast, managed, in-memory caches, instead of relying entirely on slower disk-based databases.
Amazon Elasticsearch (OpenSearch Service) is a fully managed service that makes it easy to deploy, secure, operate, and scale Elasticsearch to search, analyze, and visualize data in real-time.
Pricing for these two services depends on several factors like instance types, number of instances, storage, data transfer, etc. More specifically:
ElastiCache Pricing: The cost is based mostly on the node types, number of nodes, and region. AWS offers a variety of node types optimized to fit different use cases, characterized by varying combinations of CPU capacity, memory, SSD-based read I/O capacity, network performance and more. On-demand pricing lets you pay as you go and is ideal for unpredictable workloads. You can find the detailed pricing here.
Elasticsearch Pricing: It mainly depends on the instance types, the nature of workload (On-Demand Instances or Reserved Instances), and additional charges for optional features such as data transfer, data storage, and snapshots. You can check out the detailed pricing here.
It’s important to note that the cost could also vary based on data transfer and other features like backups, replication, etc. Therefore, it's recommended to thoroughly assess your requirements before choosing.