Sign in with
Sign up | Sign in
Your question
Solved

Best Practices for a Storage Partition Vista/Win7 NTFS Allocation unit

Last response: in Storage
Share
August 16, 2010 5:05:01 AM

From a best practices stand point do you change cluster size/ Allocation Unit size if you will be storing mainly large files 5 MB+ Audio+Video+Images+Iso images?

Think MS default Allocation unit is probably 4k on >200 GB partitions do people increase on that? 8k/16/32/64k

best regards
August 16, 2010 5:24:04 AM

Yes, it is generally recommended to use 16 kb clusters or 'allocation units' in that particular case.

Benefits include:

It will shrink your MFT to one quarter of the default size, which may free more disk space than the 'wasted' space in half used clusters.

The MFT will only take one quarter the time to search as it will only be one quarter the size.

NTFS Compression and/or NTFS Encryption can not be accidentially enabled for objects on that volume.

Files that are 16kb or less can not become fragmented. (With 4kb clusters a 16kb file can be split over 4 non-contiguous clusters). --- Think about it.


In fact you could probably make the jump to 32kb or 64kb and have one eighth to one sixteenth the file table size.
m
0
l

Best solution

August 16, 2010 5:32:47 AM

==== ==== ==== ==== ==== ==== ==== ==== ====
Master File Table (MFT):
MFT size = 258.25 MB
MFT record count = 264447
MFT usage = 100%
Total MFT fragments = 2
==== ==== ==== ==== ==== ==== ==== ==== ====

Every time the cluster size doubles the various file allocation tables and/or master file tables generally shrink by half, thus they take half the time to search.

It also means there are less units to keep track of, so file allocation will be faster.


It works in reverse too, if you use 512 byte clusters (one sector per cluster, until we move to 4KB sectors) then the file allocation tables, master file tables and allocation bitmaps will take up eight times the space (versus 4kb or 4096 byte allocation units).

Since NTFS handles files under 1kb in a special way, and folders too there is no point ever using clusters smaller than 2kb in any *possible* scenario.

Microsoft permitted 512 byte clusters so it was easier to code FAT16 and FAT32 to NTFS conversion utilities - there is no other technical or practical reason behind going smaller.


Tip: You may also want to read up on exFAT as it might suite your requirements better.
Share
August 16, 2010 8:08:48 AM

Scott2010au said:
==== ==== ==== ==== ==== ==== ==== ==== ====
Master File Table (MFT):
MFT size = 258.25 MB
MFT record count = 264447
MFT usage = 100%
Total MFT fragments = 2
==== ==== ==== ==== ==== ==== ==== ==== ====

Every time the cluster size doubles the various file allocation tables and/or master file tables generally shrink by half, thus they take half the time to search.

It also means there are less units to keep track of, so file allocation will be faster.


It works in reverse too, if you use 512 byte clusters (one sector per cluster, until we move to 4KB sectors) then the file allocation tables, master file tables and allocation bitmaps will take up eight times the space (versus 4kb or 4096 byte allocation units).

Since NTFS handles files under 1kb in a special way, and folders too there is no point ever using clusters smaller than 2kb in any *possible* scenario.

Microsoft permitted 512 byte clusters so it was easier to code FAT16 and FAT32 to NTFS conversion utilities - there is no other technical or practical reason behind going smaller.


Tip: You may also want to read up on exFAT as it might suite your requirements better.



on my 300 GB storage drive using NTFS NTFSinfo

NTFS Information Dump V1.01
Copyright (C) 1997 Mark Russinovich
http://www.sysinternals.com

Volume Size
-----------
Volume size : 307195 MB
Total sectors : 629137407
Total clusters : 78642175

Allocation Size
----------------
Bytes per sector : 512
Bytes per cluster : 4096
Bytes per MFT record : 1024
Clusters per MFT record: 0

MFT Information
---------------
MFT size : 4 MB (0% of drive)
MFT zone size : 200 MB (0% of drive)


The drive holds mostly media Audio+Video and some misc files mostly >2MB am thinking bytes per cluster is the unit we are talking about in my case 4k which is the microsoft default and 4MB MFT I think is pretty decent if I say so myself

I couldn't figure out what you used to get your MFT report with a record count was it diskkeeper?

Comparing my storage drive to my boot drive is another story 450 MB MFT size on a 70 GB Partition definitely room for improvement which if my new HDD every finishes effing formatting (approx. 12hrs now) I can starting moving files around and work on optimizing my boot partition
m
0
l
August 17, 2010 12:54:25 AM

Best answer selected by enderbean.
m
0
l
August 20, 2010 2:21:02 AM

I used the output of the command line Defrag tool in Windows 7 Home Premium (no Service Packs).
m
0
l
!