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From: Andres Freund <andres@anarazel.de>
To: pgsql-hackers@postgresql.org
Subject: Re: [HACKERS] Re: Faster CREATE DATABASE by delaying fsync (was 8.4.1
	ubuntu karmic slow createdb)
Date: Tue, 29 Dec 2009 01:29:34 +0100
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Cc: Greg Stark <gsstark@mit.edu>, pgsql-performance@postgresql.org,
	Michael Clemmons <glassresistor@gmail.com>,
	Hannu Krosing <hannu@2ndquadrant.com>,
	Scott Marlowe <scott.marlowe@gmail.com>
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On Tuesday 29 December 2009 01:27:29 Greg Stark wrote:
> On Mon, Dec 28, 2009 at 10:54 PM, Andres Freund <andres@anarazel.de> wrote:
> > fsync everything in that pass.
> > Including the directory - which was not done before and actually might be
> > necessary in some cases.
> 
> Er. Yes. At least on ext4 this is pretty important. I wish it weren't,
> but it doesn't look like we're going to convince the ext4 developers
> they're crazy any day soon and it would really suck for a database
> created from a template to have files in it go missin.
Actually it was necessary on ext3 as well - the window to hit the problem just 
was much smaller, wasnt it?

Actually that part should possibly get backported.


Andres