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Date: Sun, 17 Nov 2013 09:02:49 -0700 (MST)
From: Warren Block <wblock@wonkity.com>
To: Polytropon <freebsd@edvax.de>
Subject: Re: how install two freebsd9.2 on one disk?
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On Sun, 17 Nov 2013, Polytropon wrote:

...
> As you're probably initializing the SSD with UFS, keep in mind
> that you can apply certain optimizations to make the SSD have
> a long and happy life. :-)
>
> 	# newfs -m 0 -i 16384 -b 16384 -f 2048 -l -L os1root ada0s1
> 	# newfs -m 0 -i 16384 -b 16384 -f 2048 -l -L os2root ada0s2
>
> This is just an example which somehow corresponds to the legacy
> partitioning method mentioned above. You need of course to set
> the parameters to _your_ intended way of use!

If overriding defaults, I would make nothing less than 4K (-f above). 
But for SSDs, I just use the defaults with UFS on FreeBSD 9 and later, 
and it does not appear to be giving up SSD performance.