Stefan Kaltenbrunner <stefan(at)kaltenbrunner(dot)cc> writes:
> samples % symbol name
> 350318533 98.8618 mergepreread
> 971822 0.2743 tuplesort_gettuple_common
> 413674 0.1167 tuplesort_heap_siftup
I'm not immediately seeing why mergepreread would have such a problem
with lots of tapes. Could you reproduce this in a debug build, then
attach to the process with gdb and print out the contents of the "state"
struct?
regards, tom lane