In my oppinion, as MFT stores descriptions of all te files(name, security, list of attributes and etc.), disk defragmentation won't influence MFT content. Am i right?
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You are right in the fact that disk defragmentation should not have any relation to the MFT.
The NTFS file system reserves space for the MFT to keep the MFT as contiguous as possible as it grows. The space reserved for the MFT in each volume is called the MFT zone. Space for file and directories is allocated from it only after all of the volume space outside of the MFT zone has been allocated. The disk needs to be almost full with multiple small files for the MFT to become fragmented.
In addition, to optimize file lookups, NTFS tries to keep the MFT defragmented by not allocating clusters around the MFT to other files.
To my knowledge, the MFT zone is allocated as needed in 200 MB chunks (number maybe not up to date), sufficient for more than 200,000 files to be recorded. When the first 200 MB are full, then a new zone is allocated anywhere on the disk. You can defrag these 200 MB chunks, but this is probably not worth the bother.
harrymc
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As far as I was able to find out:
Disk Defragmenter cannot defragment the MFT once it becomes fragmented. But, because the MFT is constantly being used to access all other files on the disk, it also gradually becomes fragmented, resulting in longer disk access times and diminished performance. NTFS minimizes this impact by reserving one-eighth of the total disk space for the exclusive use of the MFT. This area of the disk—known as the MFT Zone—keeps the MFT as contiguous as possible as it grows. more here
Worth mentioning:
The MFT Zone is not subtracted from available (free) drive space used for user data files, it is only space that is used last. When the MFT needs to increase in size, for example, you created new files and directories, it is taken from the MFT Zone first, thus decreasing MFT fragmentation and optimizing MFT performance. The default MFT Zone is calculated and reserved by Ntfs.sys when it mounts the volume, and is based on volume size. You can increase the MFT Zone by means of the registry entry documented below, but you cannot make the default MFT Zone smaller than what is calculated by Ntfs.sys. Increasing the MFT Zone does not decrease in any way disk space that can be used by users for data files.
If need be, there are solutions which can defragment the MFT:
For some recommendetions, visit this question
Leshy
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