Re: Visibility map, partial vacuums

Heikki Linnakangas wrote:
> >> Also, is anything being done about the concern about 'vacuum storm'
> >> explained below?
> > 
> > I'm interested too.
> 
> The additional "vacuum_freeze_table_age" (as I'm now calling it) setting 
> I discussed in a later thread should alleviate that somewhat. When a 
> table is autovacuumed, the whole table is scanned to freeze tuples if 
> it's older than vacuum_freeze_table_age, and relfrozenxid is advanced. 
> When different tables reach the autovacuum threshold at different times, 
> they will also have their relfrozenxids set to different values. And in 
> fact no anti-wraparound vacuum is needed.
> 
> That doesn't help with read-only or insert-only tables, but that's not a 
> new problem.

OK, is this targeted for 8.4?

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