Amazon Keyspaces vs Elassandra

Amazon Keyspaces is a managed database service compatible with Apache Cassandra. It is serverless, requires no infrastructure management, and scales automatically with application demand. The service supports the Cassandra Query Language API, existing application code, Cassandra drivers, and developer tools. Tables can use on-demand read and write capacity or provisioned capacity with optional auto scaling. AWS describes single-digit-millisecond read and write performance, with no limit on table size or row count. Multi-Region deployments offer up to 99.999% availability, and table data is replicated three times across multiple Availability Zones. Keyspaces integrates with CloudWatch for performance metrics and can stream changes to Amazon OpenSearch Service. Keyspaces Streams provides change data capture, while point-in-time recovery can restore table data to any second in the preceding 35 days. Data is encrypted at rest by default, with AWS-owned or customer-managed keys. The free tier lasts for the first three months after creating the first resource, is limited to one per payer account, and includes 30 million write request units, 30 million read request units, and 1 GB of storage.

Elassandra combines Apache Cassandra’s distributed storage with embedded OpenSearch search on each node. Its maintained line targets Apache Cassandra 4.0.x, OpenSearch 1.3.x, and Java 11. OpenSearch indices map to Cassandra keyspaces, documents to rows, and indexed fields to columns or cells; the current _doc model maps to a Cassandra table. Cassandra remains the durable layer, allowing restart recovery to replay Cassandra state and rebuild a local search view. Applications can search through the OpenSearch HTTP API or CQL, with HTTP responses following OpenSearch style. Data placement uses Cassandra token ownership, while replicas follow keyspace replication. Schemas can be created from OpenSearch indexes or discovered from existing Cassandra schemas through mappings. Integrations listed include OpenSearch plugins, OpenSearch Dashboards, and Spark. Deployment options include tarball, Debian package, RPM, Docker image, and Helm chart. Elassandra is free and open source, with a 30-day trial noted.