Chapter 9. Open system servers - Windows 327
names, bad-cluster remapping, multiple data streams, general indexing of file attributes, and
POSIX. All of these contribute to making NTFS a robust file system.
Windows 2003 uses the following default cluster sizes for NTFS, as shown in Table 9-3,
where the value for number of sectors assumes a standard, 512 byte sector. On systems with
sectors that are not 512 bytes, the number of sectors per cluster may change, but the cluster
size remains fixed.
Table 9-3 NTFS default cluster sizes
These values are only used if an allocation unit size is not specified at format time, using the
/A:<size> switch with the format command.
9.3.2 Disabling short file name generation
By default, for every long file name created in Windows, NTFS generates a corresponding
short file name in the older 8.3 DOS file name convention for compatibility with older
operating systems. In many instances this functionality can be disabled, offering a
performance increase.
If you use large numbers of files in an NTFS folder (300,000 or more), disable short-file name
generation for better performance, and especially if the first six characters of the long file
names are similar.
Before disabling short name generation, make sure that there is no DOS or 16-bit application
running on the server that requires 8.3 file names, nor are there any users accessing the files
on the server via 16-bit applications.
To disable the generation of 8.3 short names, edit the following registry parameter:
HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \Control \FileSystem
Change its value from 0 to 1. In Windows Server 2003, this parameter can also be set by
using the command:
fsutil behavior set disable8dot3 1
9.3.3 Disable NTFS last access updates
Each file and folder on an NTFS volume contains an attribute called Last Access Time. This
attribute shows when the file or folder was last accessed, such as when a user performs a
folder listing, adds files to a folder, reads a file, or makes changes to a file. Maintaining this
information creates a performance overhead for the file system especially in environments
Drive size Cluster size Number of sectors
512 MB or less 512 bytes 1
513 MB to 1024 MB (1 GB) 1 K 2
1025 MB to 2048 MB (2 GB) 2 K 4
2049 MB to 2048 GB (2 TB) 4 K 8
Note: The maximum NTFS volume size as implemented in Windows Server 2003 is 2
clusters minus 1 cluster. For example, using 64-KB clusters, the maximum NTFS volume
size is 256 terabytes minus 64 KB. Using the default cluster size of 4 KB, the maximum
NTFS volume size is 16 terabytes minus 4 KB.

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