Обсуждение: question on pg_ctl

Hi Everybody,

I want to change a line in postgresql.conf (shared_buffers)
and then issue a command:
  pg_ctl reload

This forces the postmaster process to reread the configuration
file with new shared_buffer value.  And the postgres process
that comes to life from this point on will execute with the
newly specified value.  Correct?

I have jobs that have been running more than a week.  Can somebody
please tell me what happens to these processes?  Ie., (a) will they
keep running in the current mode?  (b) will the postmaster assign
more memory while they are running?

Thank you.

Regards,

Tena Sakai
tsakai@gallo.ucsf.edu

On Mon, Sep 22, 2008 at 11:49 AM, Tena Sakai <tsakai@gallo.ucsf.edu> wrote:
> Hi Everybody,
>
> I want to change a line in postgresql.conf (shared_buffers)
> and then issue a command:
>   pg_ctl reload
>
> This forces the postmaster process to reread the configuration
> file with new shared_buffer value.  And the postgres process
> that comes to life from this point on will execute with the
> newly specified value.  Correct?

To quote the postgresql.conf file:

shared_buffers = 150MB                  # min 128kB or max_connections*16kB
                                        # (change requires restart)

So it requires a complete restart.  Note that for the things you can
reload on, there's no real effect on running queries or connections
(at least no detrimental ones I can think of.)

Many thanks, Scott!

Tena


-----Original Message-----
From: Scott Marlowe [mailto:scott.marlowe@gmail.com]
Sent: Mon 9/22/2008 11:21 AM
To: Tena Sakai
Cc: pgsql-admin@postgresql.org
Subject: Re: [ADMIN] question on pg_ctl

On Mon, Sep 22, 2008 at 11:49 AM, Tena Sakai <tsakai@gallo.ucsf.edu> wrote:
> Hi Everybody,
>
> I want to change a line in postgresql.conf (shared_buffers)
> and then issue a command:
>   pg_ctl reload
>
> This forces the postmaster process to reread the configuration
> file with new shared_buffer value.  And the postgres process
> that comes to life from this point on will execute with the
> newly specified value.  Correct?

To quote the postgresql.conf file:

shared_buffers = 150MB                  # min 128kB or max_connections*16kB
                                        # (change requires restart)

So it requires a complete restart.  Note that for the things you can
reload on, there's no real effect on running queries or connections
(at least no detrimental ones I can think of.)