Re: parallel autovacuum: Propagate track_cost_delay_timing to parallel workers

Hi,

On Fri, Sep 25, 2026 at 8:41 AM Sami Imseih <samimseih(dot)pg(at)gmail(dot)com> wrote:
>
> Hi,
>
> Here is a small patch to propagate track_cost_delay_timing to parallel
> autovacuum workers. 1ff3180ca01 propagates the cost-based delay
> parameters via PVSharedCostParams but left this one out, so a worker keeps
> the value it inherited at parallel start, and workers will not report
> sleep time if the GUC is turned on mid-flight.
>
> This only impacts delay reporting, but should be backpatched to 19 which
> introduced parallel autovacuum.
>
> CC Sawada-san and Zsolt since there is a related discussion in [1], though
> that one is about throttling.

Thank you for the report and the patch! Good catch. The patch looks
good to me overall and works as expected. I have one minor comment
though:

int cost_page_miss;
+ bool track_delay_timing;
} PVSharedCostParams;

I think using track_cost_delay_timing seems better in terms of greppability.

Regards,

--
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com