Обсуждение: pg_ctl -w vs unix_socket_directory

Hello,

"pg_ctl -w -D ... start" doesn't work when unix_socket_directory is set
to somewhere else than the compiled in default ("/tmp").  Having this is
useful for the startup scripts, so the status "DONE" actually means
success, instead of "maybe".

Jeff Davis wrote about it a while ago:
http://svr5.postgresql.org/pgsql-general/2006-09/msg01141.php


Simple hacky patch for v8.2.5; maybe someone finds it useful before
the proper config parser is integrated:
http://cvs.pld-linux.org/cgi-bin/cvsweb/SOURCES/postgresql-pg_ctl-fix.patch?rev=HEAD

--
Radosław Zieliński <radek@pld-linux.org>

This has a trivial workaround - just set PGHOST for pg_ctl:

[andrew@constanza inst.codfix.5705]$ 
PGHOST=/home/andrew/pgl/inst.codfix.5705 bin/pg_ctl -D data/ -l logfile 
-w start
waiting for server to start.... done
server started
[andrew@constanza inst.codfix.5705]$

cheers

andrew


Radoslaw Zielinski wrote:
> Hello,
>
> "pg_ctl -w -D ... start" doesn't work when unix_socket_directory is set
> to somewhere else than the compiled in default ("/tmp").  Having this is
> useful for the startup scripts, so the status "DONE" actually means
> success, instead of "maybe".
>
> Jeff Davis wrote about it a while ago:
> http://svr5.postgresql.org/pgsql-general/2006-09/msg01141.php
>
>
> Simple hacky patch for v8.2.5; maybe someone finds it useful before
> the proper config parser is integrated:
> http://cvs.pld-linux.org/cgi-bin/cvsweb/SOURCES/postgresql-pg_ctl-fix.patch?rev=HEAD
>
>   

Andrew Dunstan <andrew@dunslane.net> [18-09-2007 23:42]:
> This has a trivial workaround - just set PGHOST for pg_ctl:

> [andrew@constanza inst.codfix.5705]$
> PGHOST=/home/andrew/pgl/inst.codfix.5705 bin/pg_ctl -D data/ -l logfile -w
> start

That would be fine for a particular installation, but isn't really
suitable for a startup script shipped with a linux distribution.  Sure,
a /bin/sh-based postgresql.conf parser could do the trick... but I just
don't feel like writing one. :-)

--
Radosław Zieliński <radek@pld-linux.org>

Radoslaw Zielinski <radek42@gmail.com> writes:
> "pg_ctl -w -D ... start" doesn't work when unix_socket_directory is set
> to somewhere else than the compiled in default ("/tmp").

pg_ctl not working is going to be the very least of your worries;
pretty much nothing else will either.

If you want some other socket directory, I strongly recommend setting
the path to it at compile time so that it's properly wired into libpq.
AFAICS the only value in specifying unix_socket_directory at server
start is if you actually *want* a stealth server that won't be found
by clients without manual intervention.
        regards, tom lane

Radoslaw Zielinski wrote:
> Andrew Dunstan <andrew@dunslane.net> [18-09-2007 23:42]:
>   
>> This has a trivial workaround - just set PGHOST for pg_ctl:
>>     
>
>   
>> [andrew@constanza inst.codfix.5705]$ 
>> PGHOST=/home/andrew/pgl/inst.codfix.5705 bin/pg_ctl -D data/ -l logfile -w 
>> start
>>     
>
> That would be fine for a particular installation, but isn't really
> suitable for a startup script shipped with a linux distribution.  Sure,
> a /bin/sh-based postgresql.conf parser could do the trick... but I just
> don't feel like writing one. :-)
>
>   

I think it's broken for a distro to ship with config files setting a 
socket dir other than the one they compile in.

If you don't like /tmp compile in something else. The you don't need to 
parse anything.

cheers

andrew

On 19/09/2007, Andrew Dunstan <andrew@dunslane.net> wrote:
> Radoslaw Zielinski wrote:
[...]
> > That would be fine for a particular installation, but isn't really
> > suitable for a startup script shipped with a linux distribution.  Sure,
[...]
> I think it's broken for a distro to ship with config files setting a
> socket dir other than the one they compile in.

The distro uses the default, of course.  The issue is: the startup
script stops working if a sysadmin changes it manually, for whatever
reason.

On 19/09/2007, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Radoslaw Zielinski <radek42@gmail.com> writes:
> > "pg_ctl -w -D ... start" doesn't work when unix_socket_directory is set
> > to somewhere else than the compiled in default ("/tmp").
> pg_ctl not working is going to be the very least of your worries;
> pretty much nothing else will either.

> If you want some other socket directory, I strongly recommend setting
[...]

I don't want any other socket directory.  All I want is a way to
create a working startup script: able to start/stop the server
regardless of changes in postgresql.conf and report the success or
failure.

On Tue, 2007-09-18 at 19:13 -0400, Tom Lane wrote:
> Radoslaw Zielinski <radek42@gmail.com> writes:
> > "pg_ctl -w -D ... start" doesn't work when unix_socket_directory is set
> > to somewhere else than the compiled in default ("/tmp").
> 
> pg_ctl not working is going to be the very least of your worries;
> pretty much nothing else will either.
> 

If you mean client applications won't work, that would be expected from
such a change to the server configuration.

> If you want some other socket directory, I strongly recommend setting
> the path to it at compile time so that it's properly wired into libpq.
> AFAICS the only value in specifying unix_socket_directory at server
> start is if you actually *want* a stealth server that won't be found
> by clients without manual intervention.
> 

Those arguments apply almost as well to the server port. The server port
is read from the postgresql.conf from pg_ctl, but not the socket
directory.

It's an annoyance: if you change the default socket directory, you're
probably going to break your init script (on FreeBSD you will, because
it uses "-w"). I don't think that's the expected result, and it's not
intuitive to find the cause of the problem.

I think the inconsistency between server port number and socket
directory is less than ideal. However, I also don't feel very strongly
about it. It's rare, and a there are plenty of workarounds. 

Regards,Jeff Davis