Aligning Dynamic Disks in Windows for better Performance

Disk Alignment has become very important for Windows Administrators, as this improves the performance and improves the I/O File storage and Database servers. In windows 2008 above a 1MB offset has been introduced by Microsoft, where all disk of the disk properly aligned in the back-end of the storage. Aligning Dynamic Disks   is fixed in Windows. new dynamic disks don’t have the 1MB offset at the front of the drive. If the drive uses the MBR partition, the offset will be 31KB. If the drive uses the GPT partition style, the offset will be 17KB.

Aligning Dynamic Disks in Windows

You add a new disk to Windows server and convert it to a dynamic disk .  create the simple volume on the drive.

will see something like:

Partition ### Type Size Offset
------------- ---------------- ------- -------
Partition 1 Dynamic Data 1863 GB 31 KB

OR

Partition ### Type Size Offset
------------- ---------------- ------- -------
Partition 1 Dynamic Reserved 1024 KB 17 KB
Partition 2 Reserved 127 MB 1041 KB
Partition 3 Dynamic Data 139 GB 128 MB

WARNING: This will erase the drive. These instructions are ONLY intended to be run a new drive with no data upon it.

Start off with disk part and select the appropriate drive:

list disk
select disk X
clean
online disk
attributes disk clear readonly

Convert the drive to GPT and fix the default reserved partitions to what it should be:

convert gpt
select part 1
delete part override
create partition msr size 128

This creates the reserved partition correctly with the 1MB offset. convert the drive to dynamic and create your already aligned volume:

convert dynamic
create volume simple

This will create a simple volume on the disk with correct alignment.

You Might Also like To Know….