Hi to all.
Please take a look at the initial comment contained into the logtape.c file:
http://doxygen.postgresql.org/logtape_8c-source.html
Almost at the beginning of that file, it is affirmed that implementing
tapes on disk (quote: /by creating a separate file for each "tape"/)
will require more space than implementing merge on tapes themselves.
Now, taking in account that tuplesort.c and logtape.c actually DO
implement tapes on disk, in which case it would require between 2x and
4x the input space?
Thanks for your attention.
Best regards.
Manolo