Re: How much do the hint bits help?

Merlin Moncure <mmoncure@gmail.com> writes:
> Attached is an incomplete patch disabling hint bits based on compile
> switch. ...
> So far, at least doing pgbench runs and another test designed to
> exercise clog lookups, the performance loss of always doing full
> lookup hasn't materialized.

The standard pgbench test would be just about 100% useless for stressing
this, because its net database activity is only about one row
touched/updated per query.  You need a test case that hits lots of rows
per query, else you're just measuring parse+plan+network overhead.
        regards, tom lane