File Allocation Unit Size – A Myth

The overall meaning of “Allocation Unit Size” in brief is….

The default allocation unit size on a windows drive is 4KB. When we format the drive, we can set that to a larger size – again 64KB is recommended for SQL Server data, log, and tempdb files.
The allocation unit size is basically the smallest unit of storage that any individual file can take up. If I set the allocation unit size on a drive to 64KB and then create a tiny text file which only takes up 11 bytes, that one file will take up 64KB on disk.

Continue reading


SQL Server Architecture

This page has moved here