Re: Additional size of hash table is alway zero for hash aggregates

On Thu, Mar 12, 2020 at 12:16:26PM -0700, Andres Freund wrote:
> On 2020-03-12 16:35:15 +0800, Pengzhou Tang wrote:
> > When reading the grouping sets codes, I find that the additional size of
> > the hash table for hash aggregates is always zero, this seems to be
> > incorrect to me, attached a patch to fix it, please help to check.
> 
> Indeed, that's incorrect. Causes the number of buckets for the hashtable
> to be set higher - the size is just used for that.  I'm a bit wary of
> changing this in the stable branches - could cause performance changes?

I found that it was working when Andres implemented TupleHashTable, but broke
at:

| b5635948ab Support hashed aggregation with grouping sets.

So affects v11 and v12.  entrysize isn't used for anything else.

-- 
Justin