HP LeftHand SAN Solutions Support Document - Application Notes - Best Practices for Enabling Microsoft Windows with SAN/iQ®

Table Of Contents
47
6 Chapter: Setting the Windows Disk
Partition Offset for Optimal Performance
Overview
This section describes how to configure Windows disk partitions to be aligned
optimally for LeftHand storage. Windows default partition set does not align
the partition to the physical disk that the partition is on. Correctly aligning
the partition helps reduce latency when writing to the partition by
eliminating unnecessary disk writes and reads that occur when partitions are
not aligned. For best results Windows partitions should be aligned at 64K.
Note that this can only be done when creating a new partition before
formatting. It is not possible to align a partition that has data on it already
without losing that data.
Aligning a Partition with Diskpar.exe Program for Windows 2000 or
Windows 2003, Non SP-1
Diskpar.exe is available in the windows 2000 resource kit
Obtain diskpar.exe and place it somewhere in the windows system path
Open disk management and note the physical disk number of the drive
you want to partition, in this case Disk 1.