[ale] OT: WD "Advanced Format" and "Green Drives"

[Greg Freemyer]

On Fri, Apr 9, 2010 at 5:31 PM, Michael Trausch <mike at trausch.us> wrote:
> On Fri, 2010-04-09 at 13:45 -0400, Greg Freemyer wrote:
>> I would avoid drives with 4KiB physical blocks for a while longer
>> unless you want to take extra care about alignment etc.
>
> It should not be a great issue; the only thing that you have to be sure
> about is to align the start of a partition correctly.  The ext2/3/4
> family of filesystems already uses 4KiB blocks by default for many
> configurations, and so honestly the only real care that you have to take
> is to be sure that the start of the first 4KiB block is on a native
> boundary.

Surprisingly some of the partitioning tools fail if you try to work
with partitions that don't follow their preconceptions about how the
start and end of partitions should align with cylinders.

sfdisk and cfdisk have neither been updated to be more flexible.

Below is a cut and paste from a lkml email from just last week.  Note
the fatal error at the end.

===
I created this partition table using cfdisk (util-linux 2.17 from
debian/experimental). I guess even that is too old?

I now re-created the partition table using fdisk from util-linux-ng
git and got this:

Command (m for help): p

Disk /dev/sdb: 2000.4 GB, 2000398934016 bytes
81 heads, 63 sectors/track, 765633 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x2afff6d1

  Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048  3907029167  1953513560   83  Linux

but:


$ sudo cfdisk -P s /dev/sdb
FATAL ERROR: Bad primary partition 0: Partition ends in the final
partial cylinder

===

I'm not saying its real hard to work with 4K physical sector drives,
but it does introduce problems with little or no benefit.

Or if there is benefit, what is it?

Greg