On Mon, Dec 7, 2015 at 10:36 PM, Tory M Blue <tmblue@gmail.com> wrote:
> What am I not understanding missing?
Yes. There is a hard limit on the number of tuples than can be sorted
in memory prior to PostgreSQL 9.4. It's also the case that very large
work_mem or maintenance_work_mem settings are unlikely to help unless
they result in a fully internal sort.
There is evidence that the heap that tuple sorting uses benefits from
*lower* settings. Sometimes as low as 64MB.
We're working to make this better in 9.6.
--
Regards,
Peter Geoghegan