Re: autovacuum_freeze_max_age on append-only tables

On Wed, 2022-04-20 at 23:06 +0000, senor wrote:
> I'm apparently needing an education on how this "to avoid wraparound" vacuum differs from
> any other. I've seen it referenced as "more aggressive" but I'd like details.

The difference is twofold, as far as I know:

- it will not skip any pages just because it happens not to get a lock on them
- it will refuse to die if the lock it holds on the table conflicts with a user lock

Unless you are in the habit of taking strong locks on the table, you shouldn't
notice a difference.  Anti-wraparound VACUUM is a routine activity and does not
interfere with DML, just like a normal VACUUM.

Yours,
Laurenz Albe
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