Re: pgsql: Refactor how some aux processes advertise their ProcNumber - Mailing list pgsql-committers

On Thu, Jul 9, 2026 at 9:17 PM Heikki Linnakangas <hlinnaka@iki.fi> wrote:
> Why is the autovacuum launcher not an aux process? I guess it's because
> it needs to acquire a heavy-weight lock in order to read the list of
> databases.

That seems to be one of the reasons, based on the comment about auxiliary
processes in miscadmin.h:

-------------------------
* Auxiliary processes. These have PGPROC entries, but they are not
* attached to any particular database, and cannot run transactions or
* even take heavyweight locks. There can be only one of each of these
* running at a time, except for IO workers.
-------------------------

Regards,

--
Fujii Masao