ZFS installs on HD with 4k physical blocks without any warning as on 512 block size device

Tom Evans tevans.uk at googlemail.com
Fri Aug 19 10:45:04 UTC 2011


On Thu, Aug 18, 2011 at 6:50 PM, Yuri <yuri at rawbw.com> wrote:
> Some latest hard drives have logical sectors of 512 byte when they actually
> have 4k physical sectors. Here is the document describing what to do in such
> case:
> http://ivoras.net/blog/tree/2011-01-01.freebsd-on-4k-sector-drives.html .
> For UFS: newfs -U -f 4096 /dev/da0
> For ZFS: gnop create -S 4096 /dev/da0 && zpool create data /dev/da0.nop
>
> I am sure most people just install such hard drive without doing this and
> potentially get suboptimal performance since they aren't aware about this.
> Shouldn't UFS and ZFS drivers be able to either read the right sector size
> from the underlying device or at least issue a warning?
>
> Yuri

The device never reports the actual sector size, so unless FreeBSD
keeps a database of 4k sector hard drives that report as 512 byte
sector hard drives, there is nothing that can be done.

Cheers

Tom


More information about the freebsd-hackers mailing list