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13 512e and 4Kn Disk Formats

5.4 VMware support

The key strategies in managing the transition to 4K sectors in a Windows environment also apply to

VMware. VMware is yet to show concrete plans to support 512e and 4Kn drives.

Table 4 VMware support

Operating system

512e

4Kn

VMware ESXi

TBD

5.5 Dealing with unaligned conditions

Using a 4K-aware version of an operating system to create hard drive partitions is a simple, straightforward

method for avoiding unaligned conditions. Some third-party firms offer utilities that examine existing hard

drive partitions and realign them as needed. This alternative takes additional time and adds steps to the

system building or upgrading process. Dell has been developing more sophisticated methods and design

systems to manage unaligned conditions to mitigate negative performance impacts.

5.6 512e/4Kn application support

Not all applications are 4K physical sector aware. Table 5 summarizes the 4K application support. When an

application is 512e/4Kn aware, the I/Os will be compliant to the file system partition, and the drives will run

at expected performance level.

Table 5 Application support

Application

512e

4Kn

Comments

Oracle

Yes

Microsoft Exchange

Yes

4Kn support ~2016*

SQL

Yes

VDI

TBD

*It is more of supportability issue that Microsoft has not fully tested/validated Exchange with 4Kn drives. Since

Exchange does its own replication, it is very sensitive to the disk types, in particular to disk sector sizes and does not

recommend having different disk types as part of the same Database availability group. There are issues where the

replication can fail; for example, you have a 512n disk hosting one DB copy and a 512e disk hosting another DB copy.

See the following article for more details: http://blogs.technet.com/b/exchange/archive/2013/04/24/exchange-2010-

database-availability-groups-and-disk-sector-sizes.aspx

6 Drive labels

The Advanced Format Logo Program was created by IDEMA and the Advanced Format Marketing Work

Group to easily identify hard disk drives that employ 4K sectors. While usage of the logo is optional, AF