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Date: Tue, 04 Mar 2014 11:52:38 +1100
From: Daniel O'Callaghan <danny@clari.net.au>
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Subject: Re: ZFS, GPTIDs, and using the whole disk
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Cc: Chris Stankevitz <chrisstankevitz@gmail.com>
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On 4/03/2014 10:47 AM, Chris Stankevitz wrote:
> Please identify any false statements:
> 1. ZFS prefers to use the entire disk.
Garrett Wollman(I think...) says this is false.  FreeBSD's disk 
subsystem does not change the way it behaves wrt to disks versus 
partitions.  Solaris and OpenIndiana only guarantee barrier-writes while 
still using write-cache if using the whole disk.

This is also mentioned in https://wiki.freebsd.org/ZFSTuningGuide

    "The caveat about only giving ZFS full devices is a solarism that
    doesn't apply to FreeBSD. On Solaris write caches are disabled on
    drives if partitions are handed to ZFS. On FreeBSD this isn't the case."


With this in mind, my personal preference is to use GPT partitions.

Cheers,

Danny