Thread: How to increase number of connections to 7.2.1

On Mon, 2004-10-18 at 11:15, Edwin New wrote:
> I have tried changing the value of max_connections in
> Postgresql.conf.  It was commented out (as are all other entries
> except "tcpip_socket = true").  Setting it to any other value that the
> default 32 resulted in the server failing to restart.

Without knowing the error message you got, it's possible that you didn't
increase shared_buffers to correspond to the newly increased
max_connections. If you increase shared_buffers, then you're probably
exceeding the system SysV shared memory restrictions. See

http://www.postgresql.org/docs/7.4/static/kernel-resources.html#SYSVIPC

-Neil

Edwin New <edwin_new@toll.com.au> writes:

>    I need to increase the number of connections to PostgreSQL 7.2.1.
>
>
>    I have tried changing the value of max_connections in
>    Postgresql.conf.  It was commented out (as are all other entries
>    except "tcpip_socket = true").  Setting it to any other value that the
>    default 32 resulted in the server failing to restart.

1) Make sure your shared_buffers setting is big enough to handle your
   desired connection limit.

2) Make sure your kernel's shared memory limits allow for your
   shared_buffers setting.

If you can't get it to start, please post the server log entries from
the failed attempt--otherwise we have nothing to go on.

-Doug
--
Let us cross over the river, and rest under the shade of the trees.
   --T. J. Jackson, 1863

What error do you get when the server fails to restart? It sounds like
it could be a kernel resource issue. See:

http://www.postgresql.org/docs/7.4/static/kernel-resources.html

-tfo

On Oct 17, 2004, at 8:15 PM, Edwin New wrote:

> I need to increase the number of connections to PostgreSQL 7.2.1.
>
>  
>
> I have tried changing the value of max_connections in
> Postgresql.conf.  It was commented out (as are all other entries
> except "tcpip_socket = true").  Setting it to any other value that the
> default 32 resulted in the server failing to restart.
>
>  
>
> I know we should upgrade from 7.2.1 and that is going to happen soon,
> but this is a production server and I need a solution sooner.
>
>  
>
> Thanks in advance,
>
> Edwin New
> Analyst Programmer

It was the shared buffers.  Thanks to everyone for your quick and accurate responses.

Regards,

Edwin.

-----Original Message-----
From: Doug McNaught [mailto:doug@mcnaught.org]
Sent: Monday, 18 October 2004 11:45 AM
To: Edwin New
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] How to increase number of connections to 7.2.1

Edwin New <edwin_new@toll.com.au> writes:

>    I need to increase the number of connections to PostgreSQL 7.2.1.
>
>
>    I have tried changing the value of max_connections in
>    Postgresql.conf.  It was commented out (as are all other entries
>    except "tcpip_socket = true").  Setting it to any other value that the
>    default 32 resulted in the server failing to restart.

1) Make sure your shared_buffers setting is big enough to handle your
   desired connection limit.

2) Make sure your kernel's shared memory limits allow for your
   shared_buffers setting.

If you can't get it to start, please post the server log entries from
the failed attempt--otherwise we have nothing to go on.

-Doug
--
Let us cross over the river, and rest under the shade of the trees.
   --T. J. Jackson, 1863