Jan Wieck <JanWieck@Yahoo.com> writes:
> Shridhar Daithankar wrote:
>> Umm.. What does FSM does then? I was under impression that FSM stores page
>> pointers and vacuum work on FSM information only. In that case, it wouldn't
>> have to waste time to find out which pages to clean.
> It's the other way around! VACUUM scan's the tables to find and reclaim
> free space and remembers that free space in the FSM.
Right. One big question mark in my mind about these "partial vacuum"
proposals is whether they'd still allow adequate FSM information to be
maintained. If VACUUM isn't looking at most of the pages, there's no
very good way to acquire info about where there's free space.
regards, tom lane