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Partition alignment offset and Allocation unit size in Windows 2003 Server system with SQL 2005 DB


I've a couple of Windows 2003 servers with SQL 2005 DB installed and I plan to install some new ones. They are all VMware virtual machines and they have usually 3 partitions: C: with system, D: with SQL database and E: with some installation files. I've searched in google that to get better performance of system and DB I should customize partition(s) allignment offset.

A couple of advices I could find in this article: http://www.experts-exchange.com/Storage/Misc/Q_23977512.html?sfQueryTermInfo=1+64+align+offset

So... I've made use of Dell's advice and fixed allocation unit size for partition on which SQL DB resides to 64K. Partition's alignment offset has been set to 64K as well. My questions are:

- Should I also setup the same offset for C: partition (where system resides)? What about allocation unit size for C partition?
- Does somebody have a link to webpage where partition alignment, offsets and all this stuff is described in a pretty simple way?

1 Solution
"Should I also setup the same offset for C: partition (where system resides)? "

It is not neccessary however it doesn't hurt at all, and it is better to do it than not to do.  Select offset equal to cluster size or its multiply. But do not expect any fabulous performance gains due to partition aligment
"What about allocation unit size for C partition"

Bigger allocation unit (cluster size) - more space is wasted -especially in each place when ther is a big numbe of small files - and system partition it is such a a place where you will have a lot of small files. Even 1 byte file will take one cluster.  Moreover writting such a file requires to write 64kB of data - quite a big overhead, isn' it ?

I would rather go for standard NTFS 4kB cluster for system partition.

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