Re: [HACKERS] POC: Sharing record typmods between backends

On 2017-08-12 22:52:57 -0400, Robert Haas wrote:
> On Fri, Aug 11, 2017 at 9:55 PM, Andres Freund <andres@anarazel.de> wrote:
> > Well, most of the potential usecases for dsmhash I've heard about so
> > far, don't actually benefit much from incremental growth. In nearly all
> > the implementations I've seen incremental move ends up requiring more
> > total cycles than doing it at once, and for parallelism type usecases
> > the stall isn't really an issue.  So yes, I think this is something
> > worth considering.   If we were to actually use DHT for shared caches or
> > such, this'd be different, but that seems darned far off.
> 
> I think it'd be pretty interesting to look at replacing parts of the
> stats collector machinery with something DHT-based.

That seems to involve a lot more than this though, given that currently
the stats collector data doesn't entirely have to be in memory. I've
seen sites with a lot of databases with quite some per-database stats
data. Don't think we can just require that to be in memory :(

- Andres