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From: Andres Freund <andres@anarazel.de>
To: pgsql-performance@postgresql.org
Subject: Re: Re: Faster CREATE DATABASE by delaying fsync (was 8.4.1 ubuntu
	karmic slow createdb)
Date: Wed, 20 Jan 2010 05:01:55 +0100
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Cc: Greg Stark <gsstark@mit.edu>, pgsql-hackers@postgresql.org,
	Michael Clemmons <glassresistor@gmail.com>,
	Hannu Krosing <hannu@2ndquadrant.com>,
	Scott Marlowe <scott.marlowe@gmail.com>
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Hi Greg,

On Monday 18 January 2010 17:35:59 Greg Stark wrote: 
> 2) Why does the second pass to do the fsyncs read through fromdir to
> find all the filenames. I find that odd and counterintuitive. It would
> be much more natural to just loop through the files in the new
> directory. But I suppose it serves as an added paranoia check that the
> files are in fact still there and we're not fsyncing any files we
> didn't just copy. I think it should still work, we should have an
> exclusive lock on the template database so there really ought to be no
> differences between the directory trees.
If it weren't safe we would already have a big problem....

Andres