Re: Reopen logfile on SIGHUP

Andres Freund <andres@anarazel.de>

From: Andres Freund <andres@anarazel.de>
To: Greg Stark <stark@mit.edu>
Cc: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2018-02-27T22:46:23Z
Lists: pgsql-hackers
On 2018-02-27 22:32:41 +0000, Greg Stark wrote:
> On 27 February 2018 at 14:41, Anastasia Lubennikova
> <a.lubennikova@postgrespro.ru> wrote:
> 
> > Small patch in the attachment implements logfile reopeninig on SIGHUP.
> > It only affects the file accessed by logging collector, which name you can
> > check with pg_current_logfile().
> 
> HUP will cause Postgres to reload its config files. That seems like a
> fine time to reopen the log files as well but it would be nice if
> there was also some way to get it to *just* do that and not reload the
> config files.

Is that an actually important thing to be able to do?


> I wonder if it would be easiest to just have the syslogger watch for
> some other signal as well (I'm guessing the the syslogger doesn't use
> relcache invalidations so it could reuse USR1 for example). That would
> be a bit inconvenient as the admins would have to find the syslogger
> and deliver the signal directly, rather than through the postmaster
> but it would be pretty easy for them.

-many. We have been "signal starved" a number of times, and definitely
shouldn't waste one on this.

- Andres


Commits

  1. Implement "pg_ctl logrotate" command