Disable indexes on Amazon RDS PostgreSQL instance
As @pietrop already said: it's a good pratice drop de index and recreate it after the data load.

If you are loading a lots of data, use COPY[1] instead of INSERTs. Consider using PGLoader[2] on huge data load environments.

Hope it helps.

References:


https://www.postgresql.org/docs/current/static/sql-copy.html
http://pgloader.io