Re: Core Extensions relocation

On 11/21/2011 11:40 AM, Bruce Momjian wrote:
> I think a question is how often people are waiting for features that
> actually can be addressed in a contrib/plugin way. My gut feeling is
> that most missing features have to be added to the server core (e.g.
> index-only scans) and are not possible to add in a contrib/plugin way.
>

Good question; let's talk about 9.0. We were building/distributing
three things for that version that poked into the server:

-Replication monitoring tools that slipped from the 9.0 schedule,
similar to what became pg_stat_replication in 9.1
-An early version of what became hot_standby_feedback in 9.1.
-pg_streamrecv

While these weren't all packaged as extensions per se, all of them used
the PGXS interface. And they all provided deployment blocking features
to early adopters before those features were available in core, in some
cases after the issues they address had been encountered in production
deployments. As I was ranting on my blog recently, I'm seeing more
complaints recently about monitoring and management features--exactly
the sort of thing that you can improve as an extension, and that the
extensions I've proposed provide--than I am over missing big features.

Index-only scans are a good example, as one of the most requested
performance feature you can only get in core (I'd put them at #2 behind
materialized views for the customers I talk to). I wouldn't bet that
they are considered more important by a typical deployment than good
built-in query profiling though. I get complaints about query
monitoring from every single PostgreSQL install, while complaints about
not having index-only scans only come from the bigger installations.
Note how demand is high enough that we have two pg_stat_statements
replacements submitted right now.

--
Greg Smith 2ndQuadrant US greg(at)2ndQuadrant(dot)com Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support www.2ndQuadrant.us