Received: from malur.postgresql.org ([217.196.149.56])
	by arkaria.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256)
	(Exim 4.89)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1hC3gj-0004rL-Qf
	for pgsql-hackers@arkaria.postgresql.org; Thu, 04 Apr 2019 14:49:57 +0000
Received: from localhost ([127.0.0.1] helo=malur.postgresql.org)
	by malur.postgresql.org with esmtp (Exim 4.89)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1hC3gi-0001nO-LQ
	for pgsql-hackers@arkaria.postgresql.org; Thu, 04 Apr 2019 14:49:56 +0000
Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29])
	by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256)
	(Exim 4.89)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1hC3gi-0001iy-9Y
	for pgsql-hackers@lists.postgresql.org; Thu, 04 Apr 2019 14:49:56 +0000
Received: from sss.pgh.pa.us ([66.207.139.130])
	by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256)
	(Exim 4.89)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1hC3gf-000438-Kc
	for pgsql-hackers@lists.postgresql.org; Thu, 04 Apr 2019 14:49:55 +0000
Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1])
	by sss.pgh.pa.us (8.14.4/8.14.4) with ESMTP id x34EnkPn005807;
	Thu, 4 Apr 2019 10:49:46 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
cc: Justin Pryzby <pryzby@telsasoft.com>, Jeff Janes <jeff.janes@gmail.com>,
        Jesper Pedersen <jesper.pedersen@redhat.com>,
        Robert Haas <robertmhaas@gmail.com>,
        "Jamison,
    Kirk" <k.jamison@jp.fujitsu.com>,
        Alvaro Herrera <alvherre@2ndquadrant.com>,
        Michael Paquier <michael@paquier.xyz>,
        "fabriziomello@gmail.com" <fabriziomello@gmail.com>,
        "pgsql-hackers@lists.postgresql.org"
 <pgsql-hackers@lists.postgresql.org>,
        Bruce Momjian <bruce@momjian.us>
Subject: Re: pg_upgrade: Pass -j down to vacuumdb
In-reply-to: <18557ba2-3ee7-9e17-44f2-e208d26b8640@2ndquadrant.com>
References: <201902010958.cf2cbi3d2ule@alvherre.pgsql>
 <bef52417-2416-cb97-afce-a351601eab43@redhat.com>
 <D09B13F772D2274BB348A310EE3027C64659E9@g01jpexmbkw24>
 <CA+TgmobMGTfkMY-isz4pLw_bfywVOqTUDcW+obeAfYSeTBJM7A@mail.gmail.com>
 <03845f77-49e7-4569-7062-8ee1fb460ec2@redhat.com>
 <30470.1553551070@sss.pgh.pa.us>
 <2c054085-0b68-c049-d6d8-8b74852b4c73@2ndquadrant.com>
 <CAMkU=1zcOfThON4p00VTWEO1xdY6R8Xbh9KSt9pZkLHq0gdE=A@mail.gmail.com>
 <da27737d-9f3e-6798-c999-4adaa22c47f5@2ndquadrant.com>
 <CAMkU=1w2Yuvz+xbCU+42pT2U3GCE0xmkaSDXCgM9CR3bt=5Crw@mail.gmail.com>
 <20190403212434.GY17544@telsasoft.com>
 <18557ba2-3ee7-9e17-44f2-e208d26b8640@2ndquadrant.com>
Comments: In-reply-to Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
	message dated "Thu, 04 Apr 2019 16:20:26 +0200"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <5805.1554389386.1@sss.pgh.pa.us>
Date: Thu, 04 Apr 2019 10:49:46 -0400
Message-ID: <5806.1554389386@sss.pgh.pa.us>
List-Id: <pgsql-hackers.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-hackers@lists.postgresql.org>
List-Owner: <mailto:pgsql-hackers-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-hackers>
Precedence: bulk

Peter Eisentraut <peter.eisentraut@2ndquadrant.com> writes:
> I think the real fix is to have pg_upgrade copy over the statistics.
> They are right there after all, just take them.

Well, it's not "just take them", we need to develop some infrastructure
that will permit coping with cross-version differences in the stats
storage.  This isn't insoluble, but it will take some work.  We had
a prior discussion that trailed off without much result:

https://www.postgresql.org/message-id/flat/724322880.K8vzik8zPz%40abook

			regards, tom lane