AWS – Introducing a new Amazon RDS Multi-AZ option with up to 2x faster transaction commit latency, automated failovers typically under 35 seconds, and readable standby instances

Amazon Relational Database Service (Amazon RDS) for PostgreSQL and for MySQL now supports a new Multi-AZ deployment option with one primary and two readable standby database (DB) instances across three Availability Zones (AZs). This deployment option is optimized for write transactions and is ideal when your workloads require lower write latency, automated failovers, and more read capacity.

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