When you are doing bulk operations, probably you require to disable Auto-commit option in PostgreSQL.
When bulk operations are going on at that time commit of individual statement is a very costly operation.
Before you start your bulk operations, you should visit my prepared nice check list for increasing the performance of bulk operations.
I have found few database developers are finding the solution to disable the auto-commit in PostgreSQL. Once you complete with your task, again you should enable it to make sure about the data durability.
You can do this using PSQL tool and It is very simple:
Login in your PSQL tool and execute below command (It is a case sensitive):
\set autocommit off;
To enable again, execute below command:
\set autocommit on;