The following are the Burstable Performance DB instance classes available:
db.t3 – Latest-generation instance classes that provide a baseline performance level, with the ability to burst to full CPU usage. These instance classes provide more computing capacity than the previous db.t2 instance classes. They are powered by the AWS Nitro System, a combination of dedicated hardware and lightweight hypervisor.
db.t2 – Current-generation instance classes that provide a baseline performance level, with the ability to burst to full CPU usage.
Note
The DB instance classes that use the AWS Nitro System (db.m5, db.r5, db.t3) are throttled on combined read plus write workload.