Claudio Freire wrote:
> A missing optimization is that having tid unification allows VACUUM to
> implement a different strategy when it needs to clean up only a tiny
> fraction of the index. It can do the lookup by key-tid instead of
> scanning the whole index, which can be a win if the index is large and
> the number of index pointers to kill is small.
Doing index cleanup by using keys instead of scanning the whole index
would be a *huge* win for many use cases. I don't think that work needs
to be related to either of these patches.
--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
