Received: from magus.postgresql.org (magus.postgresql.org [87.238.57.229])
	by mail.postgresql.org (Postfix) with ESMTP id 2A886B53E85
	for <pgsql-performance@postgresql.org>;
	Fri, 25 May 2012 12:18:51 -0300 (ADT)
Received: from momjian.us ([72.94.173.45])
	by magus.postgresql.org with esmtp (Exim 4.72)
	(envelope-from <bruce@momjian.us>) id 1SXwHr-0003gN-RN
	for pgsql-performance@postgresql.org; Fri, 25 May 2012 15:18:50 +0000
Received: from bruce by momjian.us with local (Exim 4.72)
	(envelope-from <bruce@momjian.us>)
	id 1SXwHe-0004YL-5W; Fri, 25 May 2012 11:18:30 -0400
Date: Fri, 25 May 2012 11:18:30 -0400
From: Bruce Momjian <bruce@momjian.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: "Hugo <Nabble>" <hugo.tech@gmail.com>, pgsql-performance@postgresql.org
Subject: Re: pg_dump and thousands of schemas
Message-ID: <20120525151830.GD25444@momjian.us>
References: <1337843209018-5709766.post@n5.nabble.com>
	<CAFwQ8rdZ3LjiwdDuzNR3vN=OryQ6fzDb08hzeKzNbOzrQXNPbA@mail.gmail.com>
	<CAMkU=1zgUUqT6ZPAFAMR6cFx01Bbk+y05Fmwk63PBHOMrBPPoQ@mail.gmail.com>
	<20120525035455.GC25444@momjian.us>
	<1337921645663-5709975.post@n5.nabble.com>
	<20887.1337956883@sss.pgh.pa.us>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20887.1337956883@sss.pgh.pa.us>
User-Agent: Mutt/1.5.20 (2009-06-14)
X-Pg-Spam-Score: -1.9 (-)
X-Archive-Number: 201205/141
X-Sequence-Number: 46965

On Fri, May 25, 2012 at 10:41:23AM -0400, Tom Lane wrote:
> "Hugo <Nabble>" <hugo.tech@gmail.com> writes:
> > If anyone has more suggestions, I would like to hear them. Thank you!
> 
> Provide a test case?
> 
> We recently fixed a couple of O(N^2) loops in pg_dump, but those covered
> extremely specific cases that might or might not have anything to do
> with what you're seeing.  The complainant was extremely helpful about
> tracking down the problems:
> http://archives.postgresql.org/pgsql-general/2012-03/msg00957.php
> http://archives.postgresql.org/pgsql-committers/2012-03/msg00225.php
> http://archives.postgresql.org/pgsql-committers/2012-03/msg00230.php

Yes, please help us improve this!  At this point pg_upgrade is limited
by the time to dump/restore the database schema, but I can't get users
to give me any way to debug the speed problems.

Someone reported pg_upgrade took 45 minutes because of pg_dumpall
--schema, which is quite long.

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

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