A Guide to the Optimal Performance of
Advanced Format 512e Hard Drives from Toshiba
Properly configured Advanced Format (AF) 512e hard drives
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may deliver superior performance as compared to legacy
512 byte-per-sector drive models. However, some computer operating systems (OSs) and application programs expect to
operate with 512 byte sector disk drives. To provide compatibility in such cases AF 512e drives automatically convert
512-byte data blocks from the host and store them in a 4K block on the AF 512e drive. However, for optimal performance
it is important to have proper partition boundary alignment between logical 512 byte data and the physical 4K sectors of
the AF drive. Otherwise, the misalignment increases the time required to complete the 512 byte emulation writes to the
disk which may result in a noticeable impact on system performance.
The Table
below outlines which OSs are designed to establish proper 4K partition alignment for AF 512e drives and which
can benefit from the assistance of an alignment utility for AF 512e drives.
To provide the best possible user experience, Toshiba offers the Paragon Alignment Tool for Toshiba AF 512e Drives as
a free download at www.toshibastorage.com/alignment.
The Paragon Alignment Tool for Toshiba AF 512e Drives (PAT) has been specially optimized for Toshiba AF 512e hard
drives. The PAT utility generally needs to be run once during the lifetime of the PC. However, should the OS or hard
drive be changed, or if additional partitions are created on the hard drive, or if applications are used that bypass the OS
when writing to the disk then it may be beneficial to rerun the PAT utility to help maximize system, application and drive
performance.
Table – Operating Systems and Paragon Alignment Tool Usage Recommendations
Operating System
PAT Usage Guidelines for Toshiba AF 512e Drives
Microsoft® Windows 7 Family (32- or 64-bit) – factory installed
Not necessary*
Microsoft Windows 7 Family (32- or 64-bit) – non-factory
installed
Recommended in case of upgrade to Microsoft Windows 7 from Windows
XP family.*
Recommended when installing Windows to partitions pre-created with 4K-
unaware third-party application (i.e. if not creating partitions using Windows
7 distributive DVD).*
Microsoft Windows Vista® Family (32- or 64-bit) – factory
installed
Not necessary*
Microsoft Windows Vista® Family (32- or 64-bit) – non-factory
installed
Recommended in case of upgrade to Microsoft Windows Vista® from
Windows XP family.*
Recommended when installing Windows to partitions pre-created with 4K-
unaware third-party application (i.e. if not creating partitions using Windows
Vista distributive DVD).*
Microsoft Windows XP Family (32- or 64-bit)
Recommended*
Microsoft Windows 2003 Family
Recommended*
Microsoft Windows Home Server
Recommended*
Microsoft Windows Server 2008
Not necessary*
Microsoft Windows Server 2008 R2
Not necessary*
Other Microsoft Windows OSs not listed above
Upgrading to an OS listed in this table is recommended if using AF drives
NOTE: PAT may not be suitable for Toshiba AF 512e drive alignment activities involving multiple client systems or disk image cloning
(see PAT FAQ for more detail).
NOTE: When encrypting the contents of an entire hard drive or individual partitions, the creation and alignment of partitions should be
performed prior to deploying an encryption solution. There is a risk of data loss if PAT is used to align encrypted partitions
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Generation One AF 512e drives are denoted in Toshiba literature as “4096/512e”
*Periodic usage of the Paragon Alignment Tool for Toshiba AF 512e Drives (PAT) on systems where software and/or computer programs may issue misaligned, non-buffered writes to the hard drive may
improve the speed at which data is written by these applications. Once encryption of a hard drive or individual partitions has been performed, periodic use of PAT is not recommended due to the risk of
data loss.
Subject to Change: While Toshiba has made every effort at the time of publication to ensure the accuracy of the information provided herein, specifications, configurations,
system/component/options and availability are all subject to change without notice.
© 2011 Toshiba America Information Systems, Inc. All rights reserved.
Linux is a register trademark of Linus Torvalds. Windows is a registered trademark of Microsoft Corporation in the United States and other countries. All trademarks are
property of their respective owners.
ALIGNMENT GUIDE 03/1/2011
