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From: "Steven Hartland" <killing@multiplay.co.uk>
To: "Mark Felder" <feld@freebsd.org>,
	"Freddie Cash" <fjwcash@gmail.com>
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Subject: Re: fdisk(8) vs gpart(8), and gnop
Date: Sun, 1 Jun 2014 16:52:27 +0100
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Cc: hackers@freebsd.org, "Michael W. Lucas" <mwlucas@michaelwlucas.com>
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----- Original Message ----- 
From: "Mark Felder" <feld@freebsd.org>

> On May 31, 2014, at 20:57, Freddie Cash <fjwcash@gmail.com> wrote:
> 
>> There's a sysctl where you can set the minimum ashift for zfs. Then you
>> never need to use gnop.
>> 
>> I believe it's part of 10.0?
> 
> I've not seen this yet. What we need is to port the ability to set ashift at pool creation time:
> 
> $ zpool create -o ashift=12 tank mirror disk1 disk2 mirror disk3 disk4
> 
> I believe the Linux zfs port has this functionality now, but we still do not.

We don't have that direct option yet but you can achieve the
same thing by setting: vfs.zfs.min_auto_ashift=12

    Regards
    Steve