IO related waits

Hi,
One of our application using RDS postgres. In one of our streaming
applications(using flink) which processes 100's of millions of transactions
each day, we are using row by row transaction processing for inserting data
into the postgres database and commit is performed for each row. We are
seeing heavy IO:XactSynch wait events during the data load and also high
overall response time.

Architecture team is suggesting to enable asynch io if possible, so that
the streaming client will not wait for the commit confirmation from the
database. So I want to understand , how asynch io can be enabled and if any
downsides of doing this?

Regards
Veem