Re: Wake up autovacuum launcher from postmaster when a worker exits

On Thu, Jan 8, 2026 at 11:57 AM Heikki Linnakangas <hlinnaka(at)iki(dot)fi> wrote:
>
> When an autovacuum worker exits, ProcKill() sends SIGUSR2 to the
> launcher. I propose moving that responsibility to the postmaster, because:
>
> * It's simpler IMHO
>
> * The postmaster is already responsible for sending the signal if fork()
> fails
>
> * It makes it consistent with background workers. When a background
> worker exits, the postmaster sends the signal to the launching process
> (if requested).
>
> * Postmaster doesn't need to worry about sending the signal to the wrong
> process if the launcher's PID is reused, because it always has
> up-to-date PID information, because the launcher is postmaster's child
> process. That risk was negligible to begin with, but this eliminates
> completely, so we don't need the comment excusing it it anymore.

It sounds reasonable to me too. +1.

Regards,

--
Masahiko Sawada
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