OS block size for Linux and Windows

Determine OS block size for Linux and Windows


A block is a uniformly sized unit of data storage for a filesystem. Block size can be an important consideration when setting up a system that is designed for maximum performance.


Block size in Linux : If we want to confirm the block size of any filesystem of Ubuntu or any other Linux OS, tune2fs command is here to help:

ubuntu# tune2fs -l /dev/sda1 | grep Block
Block count: 4980736
Block size: 4096
Blocks per group: 32768


From this example, we can see that the default block size for the filesystem on /dev/sda1 partition is 4096 bytes, or 4k. That's the default block size for ext3 filesystem.

OS block size in Solaris :

$perl -e '$a=(stat ".")[11]; print $a'
8192

or
$df -g | grep 'block size'

Block size in Window Machine : If OS is using ntfs system use the below command :

C:\>fsutil fsinfo ntfsinfo D:
NTFS Volume Serial Number : 0x7a141d52141d12ad
Version : 3.1
Number Sectors : 0x00000000036b17d0
Total Clusters : 0x00000000006d62fa
Free Clusters : 0x00000000001ed190
Total Reserved : 0x0000000000000170
Bytes Per Sector : 512
Bytes Per Cluster : 4096 <<=== (block size)
Bytes Per FileRecord Segment : 1024
Clusters Per FileRecord Segment : 0
Mft Valid Data Length : 0x0000000005b64000
Mft Start Lcn : 0x00000000000c0000
Mft2 Start Lcn : 0x000000000036b17d
Mft Zone Start : 0x000000000043c9c0
Mft Zone End : 0x000000000044b460