AWS Certified SysOps Administrator – AssociateCost and Performance OptimizationMedium
A large enterprise is migrating a critical on-premises database to Amazon RDS for PostgreSQL. The database is highly transactional and requires extremely low latency and high throughput for both reads and writes. The current on-premises storage uses enterprise-grade SSDs with millions of IOPS. Which Amazon RDS storage type should be selected to meet these performance requirements on AWS?
- AGeneral Purpose SSD (gp2)
- BMagnetic
- CGeneral Purpose SSD (gp3)
- DProvisioned IOPS SSD (io1)
Show answer & explanationAnswer & explanation
Correct answer: D. Provisioned IOPS SSD (io1)
Provisioned IOPS SSD (io1/io2) volumes are designed for critical, high-performance transactional workloads that require consistent, low-latency performance and high throughput. They allow you to specify an exact IOPS rate, ensuring the database can handle millions of IOPS as required by the legacy system.
Why the other options are wrong
- A. General Purpose SSD (gp2) offers a baseline performance with burst capability, but its maximum IOPS is typically much lower than what's needed for 'millions of IOPS' and 'extremely low latency'.
- B. Magnetic storage is a legacy option with the lowest performance and is unsuitable for high-transactional databases requiring high IOPS and low latency.
- C. General Purpose SSD (gp3) allows for independent scaling of IOPS and throughput from storage size, offering better performance than gp2, but still may not reach the 'millions of IOPS' requirement for extremely high-performance databases.
RDS Provisioned IOPS (io1/io2)
A high-performance storage option for Amazon RDS, designed for critical, I/O-intensive database workloads requiring consistent, low-latency, and high-throughput I/O.
- Performance is specified and guaranteed in IOPS.
- Ideal for transactional databases (OLTP) and other I/O-intensive applications.
- Supports very high IOPS (up to 256,000 IOPS for io1, higher for io2 Block Express).
Memory trick: RDS storage: GP for general, PIOPS for power.