Re: Idea for getting rid of VACUUM FREEZE on cold pages

On 5/25/10 10:04 PM, Heikki Linnakangas wrote:
> On 25/05/10 23:56, Josh Berkus wrote:
>> Do we get a bit in the visibility map for a page which has aborted
>> transaction rows on it?
> 
> If there's a tuple with an aborted xmin on a page, the bit in the
> visibility map is not set. A tuple with aborted xmax doesn't matter.

Then it seems like pages in the visibility map, at least, would not need
to be vacuumed or frozen.  Do pages persist in the visibility map
indefinitely?

--                                  -- Josh Berkus                                    PostgreSQL Experts Inc.
                        http://www.pgexperts.com