Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Z4beG-0004gX-48 for pgsql-docs@arkaria.postgresql.org; Mon, 15 Jun 2015 21:10:28 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1Z4beF-0001Zt-Gb for pgsql-docs@arkaria.postgresql.org; Mon, 15 Jun 2015 21:10:27 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1Z4beE-0001Zn-Pz for pgsql-docs@postgresql.org; Mon, 15 Jun 2015 21:10:26 +0000 Received: from mail-ie0-x231.google.com ([2607:f8b0:4001:c03::231]) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84) (envelope-from ) id 1Z4be6-0006iX-4u for pgsql-docs@postgresql.org; Mon, 15 Jun 2015 21:10:25 +0000 Received: by iesa3 with SMTP id a3so540174ies.2 for ; Mon, 15 Jun 2015 14:10:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=fwQIRGvLD9jw2x9t6t+7swOP0eeinirTPqdAVZXwjbw=; b=t/7GSIz+OE2xrgRm6RwQOcMizQ1sS6LlgghOtjYPNGb+qwDQvRFCEeBlxwQtmKRSwF Mxcv5vrC+x1CAgFM8GVfiaVMiLdJq7NkVhpc7JLOq+RZ7PDqHBbf1I7CyUZu1AKFGYd1 JlSuPPLnAw4rGfuQFeUdCjgBeVODJU+mCUhDIWCJke97VpH9S1x9UJLHRR4JTcfaxZVW MVsfP06Nrp5xslTQafmheFTIDKH94vtiAW7dGPThnHqi/v76n72qoZ3p/ogGrxjQRTuB sGFjNAy/S+59wSJTJnflJC2JZzK/nJFo70BI4cEXZFC0SARdayDr6uoe0g5bweFvg5Ca B5RA== MIME-Version: 1.0 X-Received: by 10.107.152.14 with SMTP id a14mr35843642ioe.92.1434402616605; Mon, 15 Jun 2015 14:10:16 -0700 (PDT) Received: by 10.36.196.7 with HTTP; Mon, 15 Jun 2015 14:10:16 -0700 (PDT) In-Reply-To: <557F3C7C.2010802@timbira.com.br> References: <557F3C7C.2010802@timbira.com.br> Date: Mon, 15 Jun 2015 17:10:16 -0400 Message-ID: Subject: Re: "Alter system" command documentation From: "David G. Johnston" To: Euler Taveira Cc: Jeff Janes , "pgsql-docs@postgresql.org" Content-Type: multipart/alternative; boundary=001a11409f186d856e051894e2f3 X-Pg-Spam-Score: -2.7 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-docs Precedence: bulk Sender: pgsql-docs-owner@postgresql.org --001a11409f186d856e051894e2f3 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, Jun 15, 2015 at 4:58 PM, Euler Taveira wrote= : > On 15-06-2015 13:32, Jeff Janes wrote: > > From http://www.postgresql.org/docs/current/static/sql-altersystem.html > > > > "Values set with ALTER SYSTEM will be effective after the next server > > configuration reload (SIGHUP or pg_ctl reload), or after the next serve= r > > restart in the case of parameters that can only be changed at server > start." > > > > Isn't it unfortunate that the command used for changing the > > configuration file from within SQL mentions SIGHUP and pg_ctl reload, > > but not "select pg_reload_conf();", as a way to activate that change? > > > SIGHUP is an implementation detail. If I were to change that sentence, > my preference is replace SIGHUP with pg_reload_conf. > =E2=80=8B > =E2=80=8BI =E2=80=8B disagree on SIGHUP being an implementation detail. =E2=80=8B =E2=80=8B Using signals in IPC (inter-process communication) is a public A= PI that should be documented when applicable. Yes, various command-line and SQL commands and functions have been provided so that one does not have to use raw signals but they are still part of the public API for the application. Adding mention of pg_reload_conf may be warranted (probably is but I haven't made an independent evaluation) but removing SIGHUP is a separate concern and one that doesn't seem necessary. David J. =E2=80=8B --001a11409f186d856e051894e2f3 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
On Mon, Ju= n 15, 2015 at 4:58 PM, Euler Taveira <euler@timbira.com.br> wrote:
<= div class=3D"h5">On 15-06-2015 13:32, Jeff Janes wrote:
> From http://www.postgresql.or= g/docs/current/static/sql-altersystem.html
>
> "Values set with ALTER SYSTEM will be effective after the next se= rver
> configuration reload (SIGHUP or pg_ctl reload), or after the next serv= er
> restart in the case of parameters that can only be changed at server s= tart."
>
> Isn't it unfortunate that the command used for changing the
> configuration file from within SQL mentions SIGHUP and pg_ctl reload,<= br> > but not "select pg_reload_conf();", as a way to activate tha= t change?
>
SIGHUP is an implementation detail. If I were to change that se= ntence,
my preference is replace SIGHUP with pg_reload_conf.
=E2= =80=8B

=E2=80=8BI = =E2=80=8B
disagr= ee on SIGHUP being an implementation detail.
=E2=80=8B
=E2=80=8B =C2=A0= Using signals in IPC (inter-process communication) is a public API that sho= uld be documented when applicable.=C2=A0 Yes, various command-line and SQL = commands and functions have been provided so that one does not have to use = raw signals but they are still part of the public API for the application.<= /div>

Adding mention of pg_reload_= conf may be warranted (probably is but I haven't made an independent ev= aluation) but removing SIGHUP is a separate concern and one that doesn'= t seem necessary.

David J.
=E2=80=8B
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