I am about to build a SQL 2005 Server (on Server 2008 R2) as a VMware Virtual Machine. The database data files will be stored on raid 5 lun and log files will be stored on raid 10 lun using vmdk's. The san in question is an EMC CX4-120.
I have been reading best practice disk alignment articles all day and i am getting a little confused. Anyway, I have found this article "http://msdn.microsoft.com/en-us/library/dd758814.aspx
" to be of help and have decided that it will be important for me to follow its recomendation on "Essential Correlations: Partition Offset, File Allocation Unit Size, and Stripe Unit Size"
It states that "There are two correlations which when satisfied are a fundamental precondition for optimal disk I/O performance. The results of the following calculations must result in an integer value:
Partition_Offset ÷ Stripe_Unit_Size
Stripe_Unit_Size ÷ File_Allocation_Unit_Size"
I am thinking of setting the Partition_Offset of both luns to 64 KB or should i leave it at the Server 2008 default of 1024 KB? I am thinking of setting each NTFS drive File_Allocation_Unit_Size to 64KB as well, is this recomended? My last question is what is Stripe_Unit_Size and what should i be setting it to?? I dont really understand what this is.