Re: Freeze avoidance of very large table.

On 11/17/15 4:41 AM, Thom Brown wrote:
> Could someone post a TL;DR summary of what the current plan looks
> like?  I can see there is a huge amount of discussion to trawl back
> through.  I can see it's something to do with the visibility map.  And
> does it avoid freezing very large tables like the title originally
> sought?

Basically, it follows the same pattern that all-visible bits do, except 
instead of indicating a page is all-visible, the bit shows that all 
tuples on the page are frozen. That allows a scan_all vacuum to skip 
those pages.
-- 
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com