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

[Jeremy Chadwick]

On Thu, Aug 18, 2011 at 01:47:26AM -0700, Yuri 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 below advice still applies.  Do not skim the page, read it.

http://ivoras.net/blog/tree/2011-01-01.freebsd-on-4k-sector-drives.html

You will therefore have to go through some manual rigmarole (preferably
with gpart(8)) to ensure performance.  If you plan on using the disks in
ZFS, you get to go through some extra rigmarole.

Also be aware that mixed LBA sizes on things like RAID (and possibly
ZFS?) may result in abysmal performance.  I just got done assisting a
user on a forum who had horrible performance on his 2-disk RAID-1 array
driven by an Intel ICH9R using Intel's native RST driver under 64-bit
Windows.  How/why?

He bought two drives, both WD10EADS (not a typo).  However, one drive
was WD10EADS-65M2BX (firmware 01.00A01, 512 byte physical, 512 byte
logical) while the other was WD10EADS-11M2B1 (firmware 80.00A80, 4096
byte physical, 512 byte logical).

He replaced the WD10EADS-65M2BX drive with another 4KB physical drive
and his performance problem disappeared.

I only point this out because this could happen to any user.  "Oh I need
to get a replacement WD10EADS drive for my system... what the heck?!?"
This is going to confuse a lot of people, and caught me by surprise when
I saw it.  Shame on Western Digital for not adjusting the model string!

Comparatively, the WD "EARS"-model drives, however, have always been
4KByte physical / 512 byte logical.  The logical size is set to 512 to
ensure full compatibility with existing and legacy OSes.

I'm dreading the day the WD Caviar Black models succumb to all this
nonsense.

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                   Mountain View, CA, US |
| Making life hard for others since 1977.               PGP 4BD6C0CB |