Re: Default setting for enable_hashagg_disk

On Sat, Jul 18, 2020 at 11:30 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Jeff Davis <pgsql@j-davis.com> writes:
> > Yes, I think we should have that GUC (hashagg_avoid_disk_plan) for at
> > least one release.
>
> You'e being optimistic about it being possible to remove a GUC once
> we ship it.  That seems to be a hard sell most of the time.

You've said that you're +0.5 on removing this GUC, while Jeff seems to
be about -0.5 (at least that's my take). It's hard to see a way
towards closing out the hashagg_avoid_disk_plan open item if that's
our starting point.

The "do we need to keep hashagg_avoid_disk_plan?" question is
fundamentally a value judgement IMV. I believe that you both
understand each other's perspectives. I also suspect that no pragmatic
compromise will be possible -- we can either have the
hashagg_avoid_disk_plan GUC or not have it. ISTM that we're
deadlocked, at least in a technical or procedural sense.

Does that understanding seem accurate to you both?

-- 
Peter Geoghegan