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Date: Fri, 27 Mar 2009 15:25:56 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
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Subject: Re: Linux 2.6.29
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On Fri, 27 Mar 2009, Linus Torvalds wrote:
> 
> The values are: 0 = off, 1 = normal, 2 = full.

Of course, I don't actually know that "off" really means "never fsync". It 
may be that it only cuts down on the number of fsync's. I do know that 
firefox with the original defaults ("fsync everywhere") was totally 
unusable, and that got fixed.

But maybe it got fixed to "only pauses occasionally" rather than "every 
single page load brings everything to a screetching halt".

Of course, your browsing history database is an excellent example of 
something you should _not_ care about that much, and where performance is 
a lot more important than "ooh, if the machine goes down suddenly, I need 
to be 100% up-to-date". Using fsync on that thing was just stupid, even 
regardless of any ext3 issues.

		Linus