How to view the allocation unit size of a NTFS partition in Vista

I guess this is one way in which NTFS is just like almost every other FS - none of them seem to like shrinking directories.

So you should apply a high-tech method that involves using that advanced language, "BAT" :)

collapse.bat

REM Invoke as "collapse dirname"
ren dirname dirname.old
mkdir dirname
cd dirname.old
move * ../dirname/
cd ..
rmdir dirname.old

Make sure you read the Microsoft's Predeployment I/O Best Practices

It recommends using 64K allocation units for NTFS volumes.

Also, read SQL Server 2000 IO basics

Finally have a look at this post.

SQL Servers page size is in fact 8K, this is non-configurable. The advantage of having larger allocation unit on the OS is that perhaps you can get slightly better performance when SQL Server is fetching pages in to its cache.

From my experience, I doubt mucking around with these values will give you any noticeable performance improvements best case you would get a minuscule improvement.

Better spend your efforts doing stuff like isolating tempdb, ensuring raid1/0 array are used, having your transaction log live on a different array to the data file and optimizing queries.