> > Whereas if you set toast_tuples_per_page to 8k then the only option > > for Postgres will be to put each datum in its own page and > waste 1-3k > > on every page. > > No, because actually the code is designed to make the toast > chunk size just enough less than 8K that the tuples fit.
He mentioned toasted values of 6-7k each. If all values are of that size (like payment slip tiffs) there is nothing we would do with the remaining 1-2k on each page. But that disadvantage disappears as soon as you have just a little more variability in the length. Still, it might be enough to opt for some freespace reuse smarts if we can think of a cheap heuristic. But the cost to fetch such a "distributed" tuple would be so huge I doubt there is anything to win but disk space. Andreas ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
