Re: work_mem greater than 2GB issue

wickro <robwickert@gmail.com> writes:
> So this is a planning mistake? Should a hash be allowed to grow larger
> than work_mem before it starts to use the disk?

HashAggregate doesn't have any ability to spill to disk.  The planner
will not select a HashAggregate if it thinks the required hash table
would be larger than work_mem.  What you've evidently got here is a
misestimate of the required hash table size, which most likely is
stemming from a bad estimate of the number of groups.  How does that
estimate (12617088 here) compare to reality?  Have you tried increasing
the statistics target for partner_id and keyword (or the whole table)?

            regards, tom lane