The database system is generally an important part of an IT system and has high requirements on storage I/O performance. You can select a storage type based on service demands. You cannot change the storage type after the DB instance is created.

Description

RDS supports Cloud SSD and Extreme SSD to suit different performance requirements of your workloads.

Cloud SSD
Stores data in cloud disks for decoupled storage and compute. The maximum throughput is 350 MB/s.
Extreme SSD
Uses 25GE network and RDMA technologies to provide you with up to 1,000 MB/s throughput per disk and sub-millisecond latency.

Performance Comparison

**Table 1** Performance comparison
Item	Cloud SSD	Extreme SSD
I/O performance	Subpar I/O performance due to additional network I/O overheads	Higher I/O performance than cloud SSDs
Elastic scalability	Scaling in seconds	Scaling in seconds
Maximum IOPS	50,000	128,000
Maximum throughput	350 MiB/s	For specifications with more than 32 vCPUs, the maximum throughput is 1,000 MiB/s. For specifications with 32 vCPUs or fewer, the maximum throughput may not reach 1,000 MiB/s due to the underlying architecture.
Read/write latency	Medium	Medium

DB Instance Storage Types

Description

Performance Comparison