On Fri, Apr 8, 2022 at 12:57 PM Peter Geoghegan <p...@bowt.ie> wrote: > What do you mean about wasting space? Wasting space on the stack? I > can't imagine you meant wasting space on the page, since being able to > accomodate more items on each heap page seems like it would be > strictly better, barring any unintended weird FSM issues.
I meant wasting space in the page. I think that's a real concern. Imagine you allowed 1000 line pointers per page. Each one consumes 2 bytes. So now you could have ~25% of each page in the table storing dead line pointers. That sounds awful, and just running VACUUM won't fix it once it's happened, because the still-live line pointers are likely to be at the end of the line pointer array and thus truncating it won't necessarily be possible. -- Robert Haas EDB: http://www.enterprisedb.com
