Aurora MySQL vs RDS: Choosing the Right Database for Moodle LMS
Performance benchmarks and cost analysis for running Moodle on Aurora MySQL versus standard RDS instances.
Choosing the right database engine is critical for Moodle performance. After running extensive benchmarks across multiple client deployments, we have clear data on when Aurora MySQL outperforms standard RDS and when the cost difference is not justified.
Performance Benchmarks
We tested both database engines under realistic Moodle workloads with 10,000 concurrent users. Aurora MySQL consistently delivered 3x faster read performance due to its distributed storage architecture. Write performance was comparable for most operations, with Aurora pulling ahead for burst workloads thanks to its auto-scaling storage IOPS.
Cost Analysis
Aurora MySQL instances cost approximately 20% more per hour than equivalent RDS instances. However, when you factor in the reduced need for read replicas, the total cost of ownership can be lower for high-traffic Moodle deployments. For smaller deployments under 1,000 users, standard RDS remains the more cost-effective choice.
High Availability & Failover
Aurora MySQL provides superior high availability with automatic failover typically completing in under 30 seconds. The storage layer replicates data six ways across three Availability Zones. RDS Multi-AZ deployments offer similar protection but with longer failover times of 60-120 seconds. For mission-critical Moodle deployments where every second of downtime impacts learners, Aurora's faster failover is a significant advantage.
Scaling Considerations
Aurora MySQL supports up to 15 read replicas with minimal replication lag, making it ideal for read-heavy Moodle workloads like course browsing and content delivery. Aurora Serverless v2 offers automatic scaling for unpredictable workloads, such as exam periods when usage spikes dramatically. RDS requires manual intervention to add read replicas and does not offer serverless options for MySQL.
Our Recommendation
For enterprise Moodle deployments serving more than 5,000 concurrent users, Aurora MySQL is the clear winner. The performance gains, built-in high availability, and automated failover justify the premium. For smaller institutions, RDS MySQL with Multi-AZ provides a solid foundation at a lower price point.