Re: Skipping VACUUM of indexes when no work required

Simon Riggs <simon@2ndquadrant.com> writes:
> We discussed an optimization of VACUUM here
> http://archives.postgresql.org/pgsql-hackers/2005-09/msg00046.php
> that would allow VACUUM to complete faster by avoiding scanning the
> indexes when no rows were removed from the heap by the VACUUM.

After looking at this, I think it is salvageable, but the patch as
written complicates the vacuum-to-index-AM API more than necessary;
there's no reason why the AM has to expose the fact that it skipped
doing anything.

I'll clean it up and reapply.

            regards, tom lane