Re: Vacuum, visibility maps and SKIP_PAGES_THRESHOLD

On 03.06.2011 22:16, Bruce Momjian wrote:
> I realize we just read the pages from the kernel to maintain sequential
> I/O, but do we actually read the contents of the page if we know it
> doesn't need vacuuming?

Yes.

>  If so, do we need to?

Not necessarily, but it allows us to freeze old tuples, and doesn't cost 
much anyway.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com