Jepsen: Amazon RDS for PostgreSQL 17.4

1 Background PostgreSQL is a popular open source general-purpose SQL database. It uses multiversion concurrency control (MVCC) to provide three levels of transaction isolation. PostgreSQL’s “Read Uncommitted” and “Read Committed” are both Read Committed. The “Repeatable Read” level actually provides Snapshot Isolation, not Repeatable Read. “Serializable” provides Serializability. Amazon RDS for PostgreSQL is an AWS service which provides managed PostgreSQL clusters. RDS automates provisioning, storage management, replication, backups, upgrades, and more. Multi-AZ deployments distribute database nodes across multiple availability zones, reducing the probability of correlated failure. RDS uses synchronous replication to ensure that transactions are durable both on primary and (at least one) secondary instances before acknowledging. From a user perspective, Amazon RDS for PostgreSQL provides a pair of URLs which speak the PostgreSQL wire protocol: a primary endpoint for read-write tran ... Read full article.