Received: from makus.postgresql.org ([98.129.198.125])
	by malur.postgresql.org with esmtp (Exim 4.72)
	(envelope-from <bruce@momjian.us>) id 1T7ClG-00052q-SG
	for pgsql-docs@postgresql.org; Thu, 30 Aug 2012 21:58:51 +0000
Received: from momjian.us ([72.94.173.45])
	by makus.postgresql.org with esmtp (Exim 4.72)
	(envelope-from <bruce@momjian.us>) id 1T7ClF-0007P6-9F
	for pgsql-docs@postgresql.org; Thu, 30 Aug 2012 21:58:50 +0000
Received: from bruce by momjian.us with local (Exim 4.72)
	(envelope-from <bruce@momjian.us>)
	id 1T7ClE-0001OJ-Oj; Thu, 30 Aug 2012 17:58:48 -0400
Date: Thu, 30 Aug 2012 17:58:48 -0400
From: Bruce Momjian <bruce@momjian.us>
To: Josh Kupershmidt <schmiddy@gmail.com>
Cc: pgsql-docs <pgsql-docs@postgresql.org>
Subject: Re: Out of date advice about SIGTERM'ing backends
Message-ID: <20120830215848.GD32350@momjian.us>
References: 
 <CAK3UJRHHVHSLewwwXzKcvhKoXagxR07j=2U4P9hGqPmA=oJ1Kg@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: 
 <CAK3UJRHHVHSLewwwXzKcvhKoXagxR07j=2U4P9hGqPmA=oJ1Kg@mail.gmail.com>
User-Agent: Mutt/1.5.20 (2009-06-14)
X-Pg-Spam-Score: -2.1 (--)
X-Archive-Number: 201208/56
X-Sequence-Number: 7449

On Fri, Jun 29, 2012 at 08:10:40PM -0700, Josh Kupershmidt wrote:
> Hi all,
> 
> In the "Notes" section[0] of the postgres command's page, this advice is given:
> 
> | The postgres server uses SIGTERM to tell subordinate server
> | processes to quit normally and SIGQUIT to terminate without
> | the normal cleanup. These signals should not be used by users.
> 
> I think now that we've added pg_terminate_backend() and made it
> callable by non-superusers, we should relax the caveat against using
> SIGTERM against backends. The warning to stay away from using SIGQUIT
> seems fine as-is. Patch attached.

Patch applied for 9.3.

---------------------------------------------------------------------------


> 
> Josh
> 
> [0] http://www.postgresql.org/docs/9.2/static/app-postgres.html#AEN87192

> diff --git a/doc/src/sgml/ref/postgres-ref.sgml b/doc/src/sgml/ref/postgres-ref.sgml
> new file mode 100644
> index 4e5cd02..a1d014d
> *** a/doc/src/sgml/ref/postgres-ref.sgml
> --- b/doc/src/sgml/ref/postgres-ref.sgml
> *************** PostgreSQL documentation
> *** 726,739 ****
>   
>     <para>
>      To cancel a running query, send the <literal>SIGINT</literal> signal
> !    to the process running that command.
>     </para>
>   
>     <para>
> !    The <command>postgres</command> server uses <literal>SIGTERM</literal>
> !    to tell subordinate server processes to quit normally and
> !    <literal>SIGQUIT</literal> to terminate without the normal cleanup.
> !    These signals <emphasis>should not</emphasis> be used by users.  It
>      is also unwise to send <literal>SIGKILL</literal> to a server
>      process &mdash; the main <command>postgres</command> process will
>      interpret this as a crash and will force all the sibling processes
> --- 726,743 ----
>   
>     <para>
>      To cancel a running query, send the <literal>SIGINT</literal> signal
> !    to the process running that command. To terminate a backend process
> !    cleanly, send <literal>SIGTERM</literal> to that process. See
> !    also <function>pg_cancel_backend</> and <function>pg_terminate_backend</>
> !    in <xref linkend="functions-admin-signal"> for the SQL-callable equivalents
> !    of these two actions.
>     </para>
>   
>     <para>
> !    The <command>postgres</command> server uses <literal>SIGQUIT</literal>
> !    to tell subordinate server processes to terminate without normal
> !    cleanup.
> !    This signal <emphasis>should not</emphasis> be used by users.  It
>      is also unwise to send <literal>SIGKILL</literal> to a server
>      process &mdash; the main <command>postgres</command> process will
>      interpret this as a crash and will force all the sibling processes

> 
> -- 
> Sent via pgsql-docs mailing list (pgsql-docs@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-docs


-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +