WD Advanced Format: do I need to do something special?

[Xin LI]

Hi,

On Thu, Aug 18, 2011 at 1:47 AM, Yuri <yuri at rawbw.com> wrote:
> WD has sectors of the size 4kB in their latest hard drives, which is
> different from the traditional 512B.
> http://www.wdc.com/advformat
> http://wdc.custhelp.com/app/answers/detail/a_id/5655
>
> These articles assert that something special should be done in OS to enable
> high performance of such drives. For ex. WD recommends to install some
> latest drivers of particular version.
> But what about FreeBSD? Should it be configured in some special way too for
> these drive to perform well?
> Is it aware of 4kB sector size?

The FreeBSD driver detects 4k drives.

At this time as far as I know all AF drives on market advertises
512-bytes sector rather than 4k (mostly for compatibility with BIOS,
etc).  If they advertise 4k sector natively, you don't have to do
anything special but currently you need to make sure:

 - FS Partitions starts at a 4k boundary;
 - FS is aware of 4k sector, e.g. through gnop -S 4k for ZFS, which
will remember this so you don't have to do that at later time.  For
UFS you may want to specify larger fragment size and block size
(4k/32k for example).

Some newly developed application like FreeNAS already detect this and
make adjustment for you by default.  We need to check and make sure
that our base system tools, especially installer, would do that
though.

Cheers,
-- 
Xin LI <delphij at delphij.net> https://www.delphij.net/
FreeBSD - The Power to Serve! Live free or die