Hello Tom, > Well, as Greg pointed out, setting t_hoff correctly should be sufficient > for squeezing out useless padding between the tuple header and the tuple > data. The real objection here is that that's leaving most of the > possible gain still on the table. The tuple *as a whole* (header and > data both) is still going to get maxaligned when it's plopped onto a > disk page. I think that in real-world cases that's often where the > main padding cost comes in: with 23-byte tuple headers and no OIDs, > you aren't saving a thing by int-aligning t_hoff unless you have a nulls > bitmap and it's the wrong number of bytes long. > > So IMHO the real problem is over near PageAddItem.
Thanks for your feed back as well. Between you and Greg I think I finally understand the error in my thinking. I will investigate the PageAddItem() later tonight. - Ryan -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
