What is Ext3 Linux File System?

ext3 is the name of a file system used by GNU / Linux, it is an evolution of ext2, the previous file system used by default by many GNU / Linux distributions.

History

The first to have announced work on improving ext2 is Stephen Tweedie, who announced on 17 February 1999 have added a log file to ext2.

ext3 finally entered into the industrial build 2.4.15 Linux in November 2001.

Its designated successor is ext4.

Description

ext3 is an evolution of ext2 and the main difference is that it uses a log file, thus enabling it to avoid the long recovery phase during a sudden stop of the machine.

Although its performance is less appreciated than some of its competitors, such as ReiserFS and XFS, it has the major advantage they can be used from a ext2 partition, without having to save and restore data (a file system ext3 can be mounted and used as a file system ext2). All maintenance utilities for file systems ext2, as fsck can also be used with ext3.

Its advantage over ReiserFS is also journaling, is to allow the use of the software dump, widely used in business for backups.

Limitations

The maximum size that a ext3 partition can have depends on the block (16 Tio for a block of 4 KB). But if the disk is a SCSI the maximum size that it can have depends on the length of the address block SCSI protocol.

Expressed in 16-bit device can not exceed 2 Gio, 32-bit limit is 2 Tio and address only a block SCSI expressed on 64 bits used to send a volume of more than 2 Tio. But all devices or SCSI controllers or SCSI does not support 64-bit addressing. That is why some bays RAID SCSI drives require cutting volumes RAID volume of over 2 Tio. We can then aggregate with a logical volume management (LVM) to the maximum size that the ext3 volume may have.