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From: Christian Weisgerber <naddy@mips.inka.de>
Newsgroups: list.freebsd.questions
Subject: Re: How to minimize the number of writes to CF card?
Date: Wed, 26 Aug 2015 20:57:29 +0000 (UTC)
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On 2015-08-25, Matthew Seaman <matthew@FreeBSD.org> wrote:

> However, I don't think softupdates has much effect on the /number/ or
> writes made to the filesystem.  It's all about re-ordering writes to
> ensure metadata consistency.

Time to re-read Kirk's original paper.
http://www.usenix.org/publications/library/proceedings/usenix99/full_papers/mckusick/mckusick.pdf

See section 5.  Choice quote:

"Overall, 4.4BSD systems tend to require 40 percent fewer disk
 writes and complete tasks 25 percent more quickly than when using
 the default 4.4BSD fast filesystem implementation."

-- 
Christian "naddy" Weisgerber                          naddy@mips.inka.de