Re: when the startup process doesn't

On Wed, Jun 09, 2021 at 05:09:54PM +0530, Nitin Jadhav wrote:
> > + {"log_min_duration_startup_process", PGC_SUSET, LOGGING_WHEN,
> >
> > I think it should be PGC_SIGHUP, to allow changing it during runtime.
> > Obviously it has no effect except during startup, but the change will be
> > effective if the current process crashes.
> > See also: https://www.postgresql.org/message-id/20210526001359.GE3676@telsasoft.com
>
> I did not get exactly how it will change behaviour. In my
> understanding, when the server restarts after a crash, it fetches the
> value from the config file. So if there is any change that gets
> affected. Kindly correct me if I am wrong.

I don't think so. I checked and SelectConfigFiles is called only once to read
config files and cmdline args. And not called on restart_after_crash.

The GUC definitely isn't SUSET, since it's not useful to write in a (super)
user session SET log_min_duration_startup_process=123.

I've triple checked the behavior using a patch I submitted for Thomas' syncfs
feature. ALTER SYSTEM recovery_init_sync_method=syncfs was not picked up when
I sent SIGABRT. But with my patch, if I also do SELECT pg_reload_conf(), then
a future crash uses syncfs.
https://www.postgresql.org/message-id/20210526001359.GE3676@telsasoft.com

--
Justin