Re: problem with large maintenance_work_mem settings and

I wrote:
> Stefan Kaltenbrunner <stefan@kaltenbrunner.cc> writes:
>> samples  %        symbol name
>> 350318533 98.8618  mergepreread
>> 971822    0.2743  tuplesort_gettuple_common
>> 413674    0.1167  tuplesort_heap_siftup

> I don't have enough memory to really reproduce this, but I've come close
> enough that I believe I see what's happening.  It's an artifact of the
> code I added recently to prevent the SortTuple array from growing during
> the merge phase, specifically the "mergeslotsfree" logic.

I've committed a fix for this; if you're still interested, please
retest.
        regards, tom lane