Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 19 Nov 2014 08:46:07 -0800
From:      Freddie Cash <fjwcash@gmail.com>
To:        Alan Somers <asomers@freebsd.org>
Cc:        "freebsd-stable@freebsd.org List" <freebsd-stable@freebsd.org>
Subject:   Re: 10.1 geom "diskid"
Message-ID:  <CAOjFWZ6YuzFifaFV4y7idZbT6ywU0_g%2BTt3rPOrTtO_ywT-h-Q@mail.gmail.com>
In-Reply-To: <CAOtMX2ifYfmL5nUpVo7tCxD=YUykW=_EWUPHsFa6KpjpX9aU8g@mail.gmail.com>
References:  <FE4F6E61-C332-40A4-A913-281505819FA7@punkt.de> <166BD891-B686-41F9-A741-9C7E7D989CB8@punkt.de> <CAOtMX2ifYfmL5nUpVo7tCxD=YUykW=_EWUPHsFa6KpjpX9aU8g@mail.gmail.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Nov 19, 2014 at 8:08 AM, Alan Somers <asomers@freebsd.org> wrote:

> On Wed, Nov 19, 2014 at 8:55 AM, Patrick M. Hausen <hausen@punkt.de>
> wrote:
> > Now it's getting decidedly weird:
> >
> >> Am 19.11.2014 um 16:40 schrieb Patrick M. Hausen <hausen@punkt.de>:
> >>
> >> Hi, all,
> >>
> >> next question, sorry. I just created a fresh 10.1 installation
> >> with ZFS. With the last reboot after adding dedicated SSD
> >> based l2arc and zil, the underlying devices are referred to
> >> by "diskid" instead of the GPT labels I have first been using:
> >>
> >>       NAME                                STATE     READ WRITE CKSUM
> >>       zroot                               ONLINE       0     0     0
> >>         mirror-0                          ONLINE       0     0     0
> >>           gpt/disk0                       ONLINE       0     0     0
> >>           gpt/disk1                       ONLINE       0     0     0
> >>       logs
> >>         diskid/DISK-BTTV334403R7200GGNp2  ONLINE       0     0     0
> >>       cache
> >>         diskid/DISK-BTTV334403R7200GGNp1  ONLINE       0     0     0
> >>
> >> I can live with that, but I do not understand why the ada2 device
> >> changed from gpt/* to diskid/* while the others did not?
> >>
> >> /dev/gpt entries are not even present for ada2, neither are ada2p?
> >>
> >> At least the system could try to be consistent ;-)
> >
> > gnop create -S 4096 /dev/diskid/DISK-BTTV334403R7200GGNp3
> > zpool create ssd /dev/diskid/DISK-BTTV334403R7200GGNp3.nop
> > zpool export ssd
> > gnop destroy /dev/diskid/DISK-BTTV334403R7200GGNp3.nop
> > zpool import ssd
> > zpool status
>
>
> Why the gnop acrobatics?


=E2=80=8BFuture-proofing the pool.  :)  It's going to get harder and harder=
 to buy
512B harddrives, meaning that at some point, the drives will be replaced
with 4K drives, and performance will (potentially) tank on the pool=E2=80=
=8B.  If
you build the pool from the get-go with an ashift of 12 (4K sectors), then
you won't have any issues in the future.

--=20
Freddie Cash
fjwcash@gmail.com



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAOjFWZ6YuzFifaFV4y7idZbT6ywU0_g%2BTt3rPOrTtO_ywT-h-Q>