From owner-freebsd-hackers@FreeBSD.ORG  Sat May 19 13:49:49 2012
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Date: Sat, 19 May 2012 07:49:47 -0600 (MDT)
From: Warren Block <wblock@wonkity.com>
To: Matthias Apitz <guru@unixarea.de>
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Cc: User Wojtek <wojtek@wojtek.tensor.gdynia.pl>,
	Dimitry Andric <dim@freebsd.org>, freebsd-hackers@freebsd.org
Subject: Re: proper newfs options for SSD disk
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On Sat, 19 May 2012, Matthias Apitz wrote:

> El día Saturday, May 19, 2012 a las 10:40:32AM +0200, User Wojtek escribió:
>
>>> You may be able to find the exact erase block size in the technical
>>> documentation of your specific SSD.  But the manufacturers don't always
>>> tell. :)
>>> ...
>
> Hi,
>
> Some weeks ago in the context of Openmoko (my Linux based cellphone)
> I came across to this very interesting article about file systems and
> SSD; even if the article is in Linux context, it contains useful
> information about how SSD behaves when updating blocks on SSD.
>
> https://lwn.net/Articles/428584/

That's an excellent article.  It mentions a flashbench tool 
which can help determine data for a particular SSD:

git://git.linaro.org/people/arnd/flashbench.git

I haven't tried it yet.
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