pg_upgrade升级报错：Only the install user can be defined in the new cluster

报错示例:

Performing Consistency Checks
-----------------------------
Checking cluster versions                                   ok
Checking database user is the install user                  ok
Checking database connection settings                       ok
Checking for prepared transactions                          ok
Checking for reg* data types in user tables                 ok
Checking for contrib/isn with bigint-passing mismatch       ok
Checking for presence of required libraries                 ok
Checking database user is the install user                  Only the install user can be defined in the new cluster.

可能原因：

1、新版本数据库初始化用户同老版本不一致

2、新版本有创建新的超级用户