Обсуждение: How to _not_ save startup options in postmaster.opts?

Pg 14, if it matters.

When doing maintenance (including a giant pg_restore), sometime one wants to run with different configuration values (like archivemode=off, wal_level=minimal, autovacuum=off, etc).

I could edit postgresql.conf -- or have two of them: one normal, and one for doing maintenance -- but if I'm going to restart anyway, why not just pass those parameters directly to the postmaster?

Alas, those config values are remembered in postmaster.opts.  But I don't want that.

Thus: is there a way to tell pg to not put those options in postmaster.opts?

Or is this my only option before restarting for production:
which postgres > $PGDATA/postmaster.opts

Alas, those config values are remembered in postmaster.opts.  But I don't want that.

Original Message processed by david® How to _not_ save startup options in postmaster.opts? 2. November 2023, 18:01 Uhr Von Ron An Pgsql-admin

Pg 14, if it matters.

When doing maintenance (including a giant pg_restore), sometime one wants to run with different configuration values (like archivemode=off, wal_level=minimal, autovacuum=off, etc).

I could edit postgresql.conf -- or have two of them: one normal, and one for doing maintenance -- but if I'm going to restart anyway, why not just pass those parameters directly to the postmaster?

Alas, those config values are remembered in postmaster.opts.  But I don't want that.

Thus: is there a way to tell pg to not put those options in postmaster.opts?

Or is this my only option before restarting for production:
which postgres > $PGDATA/postmaster.opts

--
Born in Arizona, moved to Babylonia.

"David G. Johnston" <david.g.johnston@gmail.com> writes:
>> Alas, those config values are remembered in postmaster.opts.  But I don't
>> want that.

> I don’t know where this file is even documented ATM but my understanding is
> it just shows you the values used during the last startup.

It does more, per the pg_ctl man page:

    postmaster.opts

        If this file exists in the data directory, pg_ctl (in restart
        mode) will pass the contents of the file as options to postgres,
        unless overridden by the -o option. The contents of this file are
        also displayed in status mode.

It seems totally reasonable for "pg_ctl restart" to re-apply those
switches.  If you don't want that, don't use "restart", but stop
and start.

Or you could just remove the file.

            regards, tom lane

On 11/2/23 12:24, David G. Johnston wrote:

Alas, those config values are remembered in postmaster.opts.  But I don't want that.

I don’t know where this file is even documented ATM but my understanding is it just shows you the values used during the last startup.  It doesn’t remember anything in any real sense because it isn’t used by the system to determine what those parameter values should be during startup.

https://pgpedia.info/p/postmaster.opts.html

"postmaster.opts is a file in the data directory written after startup which contains the options used to start the postmaster process. The contents of postmaster.opts are used to ensure the postmaster process can be restarted with the same options with which it was originally started."

I've confirmed this behavior, which I why I wrote the email.

Use the -c functionality for your manual maintenance boots and just let the normal startup mechanism do whatever it does when you re-engage it.

David J.

On 11/2/23 12:42, Tom Lane wrote:

"David G. Johnston" <david.g.johnston@gmail.com> writes:

Alas, those config values are remembered in postmaster.opts.  But I don't
want that.

I don’t know where this file is even documented ATM but my understanding is
it just shows you the values used during the last startup.

It does more, per the pg_ctl man page:
    postmaster.opts
        If this file exists in the data directory, pg_ctl (in restart        mode) will pass the contents of the file as options to postgres,        unless overridden by the -o option. The contents of this file are        also displayed in status mode.

It seems totally reasonable for "pg_ctl restart" to re-apply those
switches.  If you don't want that, don't use "restart", but stop
and start.

Thanks.