On Fri, Jun 18, 2010 at 3:11 PM, mac_man2...@hotmail.it <mac_man2...@hotmail.it> wrote: > Il 18/06/2010 21:00, Robert Haas ha scritto: >> >> On Fri, Jun 18 >> Did you read the rest of the comment? It explains how the code avoids >> this... >> >> > > Robert, thanks for your reply. > I read the rest of the document, but please take in account that my question > wasn't about "avoiding". > My question is "in which cases"? > > I repeat my question. Tuplesort.c and logtape.c DO implement tapes on disk > and currently they do not request 2x or 4x of the input space: so, again, in > which case implementing tapes on disks requires between 2x and 4x of input > space?
I think that the comment is saying that it *would* take 2x or 4x the input space IF we created a separate file for each input. So instead we don't. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise Postgres Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
