From the 1st time I used Temporal (1.11.x) on AWS RDS, the CPU load issue already happened, it actually consumes the CPU of RDS much, by time, not peak immediately (even using MariaDB 10.3, MySQL 5.7 and MySQL 8.0 on different instance types)
When I compare to the same DB instance type using MySQL 8 on GCP CloudSQL, there is no issue (Temporal 1.12 and 1.13), CPU ~ 10-20% (instance has 1 vCPU)