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Date: Sun, 17 Nov 2013 17:38:09 +0100
From: Polytropon <freebsd@edvax.de>
To: Warren Block <wblock@wonkity.com>
Subject: Re: how install two freebsd9.2 on one disk?
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On Sun, 17 Nov 2013 09:02:49 -0700 (MST), Warren Block wrote:
> 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.

True, I've been missing that aspect. Depending on if it's a SSD
or a real disk (and what "age" the disk is from), different kinds
of optimization can be applied at certain levels (aligning the
partitions, parameters to initalize the file system). It's also
good if it's possible to predict the _kind of use_ the disk will
be put into, i. e. what and how many files will be stored and
what kind of "preferred" access (read, write, both) will be
present.


-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...