From owner-freebsd-fs@FreeBSD.ORG  Fri Oct  8 01:17:51 2010
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Date: Thu, 07 Oct 2010 20:56:26 -0400
From: Gary Corcoran <gcorcoran@rcn.com>
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Subject: ZFS and Samsung Spinpoint F4 4K sector drive
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I've tried to read up on the issue of using ZFS with 4K sector drives,
but haven't seen any definitive answers with regards to FreeBSD.
The Samsung Spinpoint F4 is their latest 2TB drive, which has 4K sectors
and "emulation", and no info on whether the emulation can be disabled.
But it is on sale for the next few days, and the price is very tempting.

So I would like to ask: Can these 4K drives, emulating 512 byte sectors,
be successfully used with ZFS raidz via _some_ tweak, without getting a major
slowdown?  That is, is there some sysctl, some option to zpool create, or
anything else, that can cause a zpool which uses whole disks, to be aligned
to 4K sectors in FreeBSD?

Thanks,
Gary