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Date: Sat, 29 Aug 2015 22:03:11 +0200
From: Polytropon <freebsd@edvax.de>
To: Warren Block <wblock@wonkity.com>
Cc: freebsd-questions@freebsd.org
Subject: Re: Replacing Drive with SSD
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On Fri, 28 Aug 2015 12:47:30 -0600 (MDT), Warren Block wrote:
> If you are a belt-and-suspenders type, create a smallish, maybe 4G, 
> partition on the drive that will never be used and leave it empty. 
> Don't write to it, ever.  This is called over-provisioning.  The drive 
> sees that all those blocks are free and it can swap them around for wear 
> leveling.  This can be used in addition to trim.

To extend the idea (because sometimes I am the axe-and-byrnie type):
Does this also work with _no_ partitions at all? For example, when
the device is formatted "as a whole" (dedicated), like

	# bsdlabel -w ada0
	# bsdlabel -e ada0
		set type "4.2BSD" for 'a' partition
		make 'a' same size as 'c'
		save
	# newfs -m 0 -i 16384 -b 16384 -f 2048 -U -t enable -n disable -L ssdroot /dev/ada0a
	# bsdlabel -B ada0

where /dev/ada0a has been prepared with bsdlabel to span the entire
device (as in the example) - or in this case, to be a little bit
less (4G) than the whole disk capacity?


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