Lesson 2 | Ext2 configuration, part 1 |
Objective | Use the mke2fs command to adjust the filesystem's block size. |
mke2fs Command
Linux provides a number of tools to configure and optimize filesystems. These tools, part of the
e2fsprogs
package, provide
administrators with the functionality they need to get the most out of their Linux filesystems.
The
e2fsprogs
package provides the following tools.
mke2fs
tune2fs
dumpe2fs
debugfs
We will explore
mke2fs
in this lesson and the others in the following lesson.
"block size" is "the number of bytes allocated to individually accessible units in the ext2 filesystem."
mke2fs
Use the mke2fs
command with the -b
option to adjust the ext2
filesystem's block size.
The block size should match the filesystem's expected usage, because block size directly impacts disk read and write performance.
Filesystems that have frequent, large file I/O operations, such as partitions containing executable programs, will perform better when the
block size of the filesystem is larger than the default 1024 bytes. A block size of 4096 bytes is typically used.
When using these larger block sizes, each lookup into the filesystem retrieves more data. Unfortunately, if these files aren't exact
multiples of the block size, more disk space will be wasted inside each block.
Filesystems that have many, small file I/O operations, such as partitions containing temporary files, will perform better with a smaller
block size, such as 1024 bytes. In this scenario, the smaller files and smaller block size reduces wasted bytes at the end of blocks while not
significantly affecting performance.
To use mke2fs
to adjust the block size, provide the -b
parameter and the partition name. For example, to adjust the
/dev/hda5
partition to 2048 bytes, use mke2fs -b 2048 /dev/hda5
.
Block size: Block size is the number of bytes allocated to individually accessible units in the ext2 filesystem.
The command mke2fs
is destructive. mke2fs
places a new, formatted filesystem onto the partition. If you mistakenly type the
wrong partition name, you will overwrite all existing data!
Question: Enter the command to format /dev/hdb3 with a block size of 1024 bytes.
Answer: mke2fs -b 1024 /dev/hdb3
The next lesson discusses the use of tune2fs
, dumpe2fs
, and debugfs
.