Re: Visibility map, partial vacuums

Bruce Momjian wrote:
> 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?

Yes. It's been on my todo list for a long time, and I've also added it
to the Open Items list so that we don't lose track of it.

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