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Date: Fri, 3 Feb 2012 09:43:37 -0500
From: "David Magda" <dmagda@ee.ryerson.ca>
To: "Pete French" <petefrench@ingresso.co.uk>
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Cc: freebsd-stable@freebsd.org
Subject: Re: Sector size of a zvol
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On Fri, February 3, 2012 07:25, Pete French wrote:
> So, I was trying to create a disc witha  sector size of 4096 bytes, and I
> assumed that simply creating a zvol with that blocksize would do the
> trick.
> But it appears that whatever the blocksize is on the xvol, diskinfo is
> reporting the sector size as 512 bytes.
>
> I this the intended behaviour ? I dont have a Solaris system to hand to
> test it on, so I have no ida if this is BSD specific or not.

Yes, it is intended. The pool sector size and ZFS dataset block size are
parameters are independent of each other.

AFAIK, there is no way to specify the sector size to use in a ZFS pool: it
is completely automatic when you call "zpool create". Ideally it should
query the disk about its sector size and use that, but I don't know if
that has been implemented (and can't be bothered to dig through the source
at this time :).