/A: Switch Added to FORMAT.COM (95207)


The information in this article applies to:

  • Microsoft Windows NT Server 3.1
  • Microsoft Windows NT Workstation 3.1
This article was previously published under Q95207

SUMMARY

Microsoft has added an /A: switch to the FORMAT.COM file for Windows NT. This switch allows you to specify an NTFS volume's allocation unit size (cluster size).

MORE INFORMATION

Using a larger allocation unit size speeds up bitmap searches and reduces external fragmentation, at the cost of greater internal fragmentation.

The syntax of this switch is: 
   /A:xxx
where xxx may be 512, 1024, 2048, or 4096.

The default for xxx is 512 bytes per allocation unit. In the retail release of Windows NT, the default allocation unit size will be a function of the disk size:

512 bytes for disks less than 512 MB
1024 bytes for disks from 512 MB to 1 gigabyte (GB)
2048 bytes for disks from 1 GB to 2 GB
4096 bytes for disks greater than 2 GB

Modification Type:MajorLast Reviewed:11/4/2003
Keywords:KB95207
©2003 Microsoft Corporation. All rights reserved.