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Date: Fri, 23 Nov 2012 12:49:42 +1030
From: Shane Ambler <FreeBSD@ShaneWare.Biz>
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To: Warren Block <wblock@wonkity.com>
Subject: Re: FreeBSD on SSD on ASUS P5KPL-C
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On 22/11/2012 14:49, Warren Block wrote:
> On Wed, 21 Nov 2012, Warren Block wrote:
>
>> Got a chance to set up a scratch drive and check this.  Turns out
>> I left out the step of creating a "slice" (MBR partition) to hold
>> the FreeBSD partitions.  Also, GPT labels cannot be used in an
>> MBR. Fixed below.  I will probably add this to my disk setup
>> article because it has come up more than once.
>
> The fdisk/bsdlabel section of my disk setup article has been
> rewritten to use gpart.  Feedback welcome.
>
> http://www.wonkity.com/~wblock/docs/html/disksetup.html

Something I meant to ask before - is there any benefit to following the
steps described in
http://www.aisecure.net/2012/01/16/rootzfs/

Abbreviated the steps are -
gpart add -t freebsd-zfs -l disk0 ada0
gnop create -S 4096 /dev/gpt/disk0
zpool create zroot /dev/gpt/disk0.nop
zpool export zroot
gnop destroy /dev/gpt/disk0.nop
zpool import zroot

The step of using gnop is meant to trick zfs into believing the disk has
4K sector size to improve performance, which I would think zfs would be
able to figure out by talking to the disk.

Does partitioning hide the sector size or would the step of aligning
the partition start to a 4k sector unhide the 4k size?
Or are these steps just a waste of time?