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Mee
Asked: 2009-09-15 17:10:10 +0800 CST

How can I get the cluster size on Windows 2008?

  • 772

This should be really simple but I can't just figure it out. I want to get the cluster size for a partition, e.g. 512, 1024, 2048 .. etc. How can I get this?

On my Windows XP I use a small utility called TreeSize to get the cluster size along with many other details, I believe it should work with Windows 2008 too but I can't believe it's not possible without a utility.

Your help is really appreciated

windows

4 Answers

  1. Best Answer

    Use the following command:

    fsutil fsinfo ntfsinfo c: (where c: is the volume/path to obtain the data for)

    This will show you smilar to the following:

    NTFS Volume Serial Number :       0x9e800d87800d675d
Version :                         3.1
Number Sectors :                  0x000000000c7fffff
Total Clusters :                  0x00000000018fffff
Free Clusters  :                  0x000000000091cfd1
Total Reserved :                  0x00000000000001b0
Bytes Per Sector  :               512
Bytes Per Cluster :               4096
Bytes Per FileRecord Segment    : 1024
Clusters Per FileRecord Segment : 0
Mft Valid Data Length :           0x0000000009fc0000
Mft Start Lcn  :                  0x00000000000c0000
Mft2 Start Lcn :                  0x0000000000c7ffff
Mft Zone Start :                  0x00000000000c9ca0
Mft Zone End   :                  0x00000000000ca7e0
RM Identifier:        07A1930B-353D-11DE-AB63-E15CC5EE82D6
    • 19

  2. You can use diskpart to do this. It's a little involved but it also prevents you from putting another utility on the server.

    Commands:

    C:\>diskpart
DISKPART>list disk

Disk ###  Status         Size     Free     Dyn  Gpt
--------  -------------  -------  -------  ---  ---
Disk 0    Online          232 GB     9 MB
Disk 1    Online          232 GB  1024 KB

DISKPART>Select disk 1 
DISKPART> list partition

Partition ###  Type              Size     Offset
-------------  ----------------  -------  -------
Partition 1    Primary            232 GB    31 KB

DISKPART> select Partition 1

Partition 1 is now the selected partition.

DISKPART> FILESYSTEMS

Current File System

Type                 : NTFS
Allocation Unit Size : 4096
Flags : 00000000

File Systems Supported for Formatting

Type                 : NTFS (Default)
Allocation Unit Sizes: 512, 1024, 2048, 4096 (Default), 8192, 16K, 32K, 64K

DISKPART>

    You want the "Allocation unit Size" entry.

    • 9

  3. You can look for a small file (~1K) and check the Size on Disk value in the properties. That will be the cluster size for the volume.

    • 7

  4. Run chdsk and look at the allocation unit size. This is the cluster size.

    • 1