Note that this in itself is not a feature but part of the infrastructure for developing parallel execution nodes (for an example, you could take a look at parallel seq scan under development[1])
Thanks for the reply. Then, my question becomes as follows: Is there a way for basic PostgreSQL users (as me) benefit from this (yet)? I don't want to dive into any codes :)
Yeah, I think this is all under the hood, so in future releases, Postgres should perform even better for you ;)
It's a framework for future functionality. End-users won't be touching it for some time I expect. The best thing about psql is their careful, iterative engineering.