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Message-ID: <4BE90E95.6060100@gmail.com>
Date: Tue, 11 May 2010 10:00:21 +0200
From: Yeb Havinga <yebhavinga@gmail.com>
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To: Kevin Grittner <Kevin.Grittner@wicourts.gov>
CC: jd@commandprompt.com, Greg Stark <gsstark@mit.edu>,
	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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	<201005101512.o4AFCZS27089@momjian.us>
	<AANLkTiktz9l00oZEjxvaMljYLebCnJQm-S9Vr4XVF071@mail.gmail.com>
	<4BE7E62C02000025000314B7@gw.wicourts.gov>
	<u2n407d949e1005101046weac382a6g99a5c932d4c5b736@mail.gmail.com>
	<1273516977.8624.18.camel@jd-desktop.unknown.charter.com>
	<4BE8118502000025000314CB@gw.wicourts.gov>
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Kevin Grittner wrote:
> "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.
>   
Would the term "entirely redundant databases" include (synchronously) 
replicated databases? (ps: I did indeed lose track about whether this is 
about fsync or full_page_writes and did not get on the track again)

regards,
Yeb Havinga