Is partition offset allignment necessary for client OS?

[kfkehua]

when you format your your VMFS datastore, it is automatically alligned to you, correct?

so when you create the client OS, say windows 2003, do you still need to perform an allignment on the client OS disk?

thx.

[geddam]

Varies on your requirement, For SQL Vms, they might require alignment in some scenarios where disk I/O latency issues are seen, However, point to note here is vmdk alignments should be done before the OS is installed. Here is a nice article on how to do that....

http://www.tcpdump.com/kb/virtualization/vmware-esx-server/vmware-disk-alignment/vmdk-windows.html

Thanks,,

Ramesh. Geddam,

VCP 3&4, MCTS(Hyper-V), SNIA SCP.

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[vmroyale]

Hello.

when you format your your VMFS datastore, it is automatically alligned to you, correct?

If you used the vSphere client to create the VMFS volume, then yes.

so when you create the client OS, say windows 2003, do you still need to perform an allignment on the client OS disk?

In Windows 2003, the boot OS partition doesn't need it. Data partitions may benefit from it, but it depends on the characteristics of the workload. It won't hurt anything to do it. Check out the Recommendations for Aligning VMFS Partitions performance study for more information. There is also some really good info in "Disk Partition Alignment Best Practices for SQL Server" at Microsoft's site.

Good Luck!