Windows 7: Best Allocation Unit Size?

jagooch · 27 Feb 2010

For my new 2TB raid 0 array? Its 4x500GB SATA drives, and I'll have a combination of small files ( like ebooks, mp3's ) and gigantic files ( CD/DVD images ) . Windows recommends an allocation unit size of 4096 bytes..should I just go with that?

I'm concerned about performance.

Dwarf · 27 Feb 2010

Hi jagooch and welcome to Windows 7 Forums

You will be fine with the recommended allocation unit size. The array will be formatted with the NTFS file system which is more efficient than the older FAT/FAT32 systems that were used in older OSes. With the older file system, as the size of the disk increased so did the allocation unit size because there was only a finite number of units that could be recorded in the allocation table. With NTFS, that limitation no longer exists (rather, it does, but it is way in excess of the size of HDDs that are available). As a result, NTFS allows you to use the space on the disk more effectively.

jagooch · 27 Feb 2010

Thanks good, it recommended 4096 , the largest was 8192, and then were were a lot of smaller sizes available. I just didn't know by what criteria to choose an optimal size.

Windows 7: Best Allocation Unit Size?

Best Allocation Unit Size? problems?