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Date: Mon, 10 May 2010 14:00:37 -0500
From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: <jd@commandprompt.com>,"Greg Stark" <gsstark@mit.edu>
Cc: "Robert Haas" <robertmhaas@gmail.com>, "Bruce Momjian" <bruce@momjian.us>,
	"Michael Tharp" <gxti@partiallystapled.com>,
	<pgsql-hackers@postgresql.org>,
	"Craig Ringer" <craig@postnewspapers.com.au>
Subject: Re: no universally correct setting for fsync
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"Joshua D. Drake" <jd@commandprompt.com> wrote:
 
> The answer to this is:
> 
> PostgreSQL.org recommends that this setting be left on at all
> times.  Turning it off, may lead to data corruption.
> 
> Anything else is circumstantial and based on knowledge and facts
> we don't have about environmental factors. 
 
Perhaps Josh's language for fsync could be modified to work here
(we're now talking about full_page_writes, for anyone who's lost
track):
 
| it is only advisable to turn off fsync if you can easily recreate
| your entire database from external data.
 
That covers bulk loads to an empty or just-backed-up database and
entirely redundant databases.  Saying it should never be turned off
would tend to make one wonder why we have the setting at all.
 
-Kevin