Re: decoupling table and index vacuum

Hi,

On 2021-04-24 11:21:49 -0700, Peter Geoghegan wrote:
> To expand on this a bit, my objection to counting the number of live
> tuples in the index (as a means to determining how aggressively each
> individual index needs to be vacuumed) is this: it's driven by
> positive feedback, not negative feedback. We should focus on *extreme*
> adverse events (e.g., version-driven page splits) instead. We don't
> even need to understand ordinary adverse events (e.g., how many dead
> tuples are in the index).

I don't see how that's good enough as a general approach. It won't work
on indexes that insert on one end, delete from the other (think
inserted_at or serial primary keys in many workloads).

Greetings,

Andres Freund