Optimize NTFS Performance (Page 3)
NTFS Compression
NTFS compression is the ability to selectively compress the contents of individual files, entire directories, or entire directory trees on an NTFS volume. NTFS compression will cause a performance degradation because a compressed file needs to be decompressed every time you access it. If you copy a compressed file, it is first decompressed, then copied, and then recompressed as a new file, adding significant CPU overhead to the process. NTFS compression runs more efficiently on Windows 2000 Professional than on Windows 2000 Server.
You can compress NTFS volumes, directories and files via the Properties dialog box in an Explorer window.
Fragmentation
When fragmentation occurs the system requires additional head and platter movements to access a file. Fragmentation can adversely affect performance. Maintaining a low level of file fragmentation on an NTFS volume is the most important way to improve volume performance. You can accomplish this maintenance by regularly running a disk-defragmentation utility, which makes every file on the volume contiguous. Only with regular use of the defragmentation tool does NTFS gain the full benefit of file defragmentation.
Windows 2000 Disk Defragmenter Tool gives you the opportunity to quickly Analyze a volume, and will advice you if defragmentation is recommended.
Disabling unnecessary NTFS behaviors
- Disable creation of short names. NTFS generates - for compatability with MS-DOS and Windows 3.x clients - the style of file name that consists of eight characters, followed by a period and a three character extension. If you don't support these types of clients. Go to HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Control \ FileSystem. Change the value of NtfsDisable8dot3NameCreation from 0 to 1
- Disable last access update. NTFS updates the date/time stamp of the last access on directories whenever it traverses the directory. This update process can slow performance on larger NTFS volumes. To disable this automatic updating, change the value of NtfsDisableLastAccessUpdate from 0 to 1, in the key HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Control \ FileSystem. If the entry is not present, add it to the registry.
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Reserve appropriate space for the Master File Table. The MFT plays an important role in the composition of an NTFS volume and its performance. The MFT continually references files as the system locates, reads, and writes the data to the disk. So the performance of the MFT is essential to the performance of the entire volume. NTFS's developers addressed potential MFT fragmentation by creating a special buffer zone around the MFT, which the NTFS volume reserves for use by the MFT. By default, this buffer zone uses approximately 12.5 percent of the disk. Although this allocation usually minimizes MFT fragmentation, sometimes the buffer zone isn't adequate. To manipulate the MFT's zone reservation, go to the HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Control \FileSystem registry key, and add a REG_DWORD value NtfsMftZoneReservation. The default value is 1, possible values are 1 to 4 (1 reserves 12.5 percent, 2 reserves 25 percent, 3 reserves 37.5 percent, and 4 reserves 50 percent of the NTFS volume for the MFT's buffer zone).
You must change this Registry setting prior to the creation of an NTFS volume. The modification affects only those volumes created after you create this Registry entry-the modification doesn't change existing NTFS volumes, which retain their original MFT zone reservations. Also, allocating more space for the MFT won't limit the amount of free disk space available for regular file storage, because NTFS will use the MFT zone if the normal user file area becomes full, which can thus be another reason why the MFT becomes fragmented. You have to keep an eye on the total space used for user files, and keep enough free space on a volume, so that the MFT can use its reserved space.
As a note to the NtfsMftZoneReservation setting, you should realize that the default setting of 12.5 percent should be sufficient for most users. If you check the Analysis Report of my volume, you will note that the MFT has a size of 74,331KB. This volume contains nearly 73,000 files, with an average file size of 111KB. Since this volume is 9GB, there will be around 1152MB reserved for the MFT, more than enough for it to grow.
