使用java awscdk，无法创建RDS 磁盘类型为pg3，强制要求设置磁盘为400GB。

[brisk233]

创建RDS 设置参数：
"rdsVersion": "13.13",
"storageType": "gp2",
"dbInstanceClass": "db.t3.micro",
"deletionProtection": false,
"cacheNodeType": "cache.t2.micro"，
"allocatedStorage": 20

提示报错内容：Failed resources:
GlbSystemIot | 17:02:09 | CREATE_FAILED | AWS::RDS::DBInstance | granwinRdsDB Resource handler returned message: "You can't specify IOPS or storage throughput for engine postgres and a storage size less than 400. (Service: Rds, Status Code: 400, Request ID: 40f52d63-ddac-4911-bba5-8015bc0d75c2)" (RequestToken: 1b930e29-348a-8e39-60ca-8c0803fb7a16, HandlerErrorCode: InvalidRequest)