Re: [BUG] Autovacuum not dynamically decreasing cost_limit and cost_delay

On Mon, Jan 23, 2023 at 12:33 PM Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org>
wrote:

> On 2021-Feb-08, Mead, Scott wrote:
>
> > Hello,
> > I recently looked at what it would take to make a running autovacuum
> > pick-up a change to either cost_delay or cost_limit. Users frequently
> > will have a conservative value set, and then wish to change it when
> > autovacuum initiates a freeze on a relation. Most users end up
> > finding out they are in ‘to prevent wraparound’ after it has happened,
> > this means that if they want the vacuum to take advantage of more I/O,
> > they need to stop and then restart the currently running vacuum (after
> > reloading the GUCs).
>
> Hello, I think this has been overlooked, right? I can't find a relevant
> commit, but maybe I just didn't look hard enough. I have a feeling that
> this is something that we should address. If you still have the cycles,
> please consider posting an updated patch and creating a commitfest
> entry.
>

Thanks! Yeah, I should be able to get this together next week.

>
> Thanks
>
> --
> Álvaro Herrera PostgreSQL Developer —
> https://www.EnterpriseDB.com/
> "Someone said that it is at least an order of magnitude more work to do
> production software than a prototype. I think he is wrong by at least
> an order of magnitude." (Brian Kernighan)
>

--
--
Scott Mead
*scott(at)meads(dot)us <scott(at)meads(dot)us>*