Unix / Linux File System
In Linux, a file system is an organized collection of files on a hard disk or partition. A partition is a region of memory that stores specialized data. Our machine's memory partitions may differ. Every partition, in general, has a file system. The general-purpose computer system must store data in a systematic manner so that we can retrieve files quickly. It saves data on hard disc drives (HDDs) or other types of storage. The file system may be kept for the following reasons:
The computer stores data mostly in RAM storage; if the computer is shut off, the data may be lost. However, there is non-volatile RAM (Flash RAM and SSD) available to keep data after a power outage. Data storage on hard drives is preferred over conventional RAM since RAM is more expensive than disk storage. Disk costs are gradually declining in comparison to RAM.
The Linux file system is divided into the following sections:
- The primary directory (/)
- A particular data storage format (EXT3, EXT4, BTRFS, XFS and so on)
- A file system-specific partition or logical disk.
Linux file system is normally a built-in layer of a Linux operating system used to handle the data management of the storage. It helps in the organizing of files on disk storage. It maintains a file's name, size, creation date, and much more information. If our file system has an unsupported file format, we can obtain software to deal with it.
Structure of Linux File System Explained
Because it has a root directory and subdirectories, the Linux file system has a hierarchical file structure. The root directory provides access to all other directories. A partition normally has one file system, although it might have many file systems.
A file system is meant to organize and offer storage space for non-volatile storage data. A namespace, which is a naming and organizational mechanism, was necessary for all file systems. The namespace specifies the naming method, the file name length, or a subset of characters that can be used in the file name. It also specifies the logical layout of files on a memory segment, such as the usage of directories for file organization. Once a namespace has been formed, a Metadata description for that specific file must be defined.
A hierarchical directory structure must be supported by the data structure ; this structure is used to indicate the available and utilized disc space for a certain block. It also includes file information such as file size, date and time of creation, update, and last updated. It also maintains advanced information about the disk portion, such as partitions and volumes. the advanced data and the structures it represents provide information about the file system stored on the disk it is separate and different from the file system metadata.
The Linux file system has a two-part software implementation design. Consider the following image:
To communicate with file system components such as files and directories, the file system requires an API (Application programming interface). API makes actions like creating, removing, and copying files easier. It facilitates an algorithm that determines how files are organized on a file system. The
first two components of the supplied file system are referred to as a Linux virtual file system. It gives the kernel and developers a single set of instructions to access the file system. To provide an interface to the file system, this virtual file system requires a specialized system driver.
What are the Features of Linux File System?
The file system in Linux produces a tree structure. All of the files are organized like a tree with branches. The root (/) directory is the uppermost directory. The root directory in Linux provides access to all other directories.
The following are some significant aspects of the Linux file system:
1. Specifying paths: Linux does not utilize the backslash () to divide components; instead, it uses the forward slash (/). For example, in Windows, the data may be saved in C: My Documents Work, but in Linux, it might be saved in /home/ My Document/ Work.
2. Partitions, Directories, and Drives: Unlike Windows, Linux does not utilize drive letters to arrange drives. We can't know if we're addressing a partition, a network device, or a “regular” directory and drive under Linux.
3. Case Sensitivity: The Linux file system recognizes the case. It differentiates between file names in lowercase and uppercase. In Linux, for example, there is a distinction between test.txt and Test.txt. This restriction also applies to Linux commands and folders.
4. File Extensions: A file on Linux may have the extension '.txt,' although it is not required that a file have a file extension. When dealing with Shell, it might be difficult for novices to distinguish between files and directories. When we use a graphical file manager, it represents the files and directories.
5. Hidden files: Linux distinguishes between normal files and hidden files, usually the configuration files are hidden in Linux OS. We usually do not need to access or read secret files. In Linux, hidden files are denoted by a dot (.) before the file name (e.g., .ignore). To access the files, we either modify the file manager's view or execute a certain command in the shell.
What are The Types of Linux File Systems?
When we install the Linux operating system, we may choose from a variety of file systems, including Ext, Ext2, Ext3, Ext4, JFS, ReiserFS, XFS, btrfs, and swap.
There are several file system types that are commonly used in Linux systems, including:
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ext2, ext3, and ext4: These are types of extended file system (ext), which is the most widely used file system for Linux systems.
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XFS: A high-performance file system that is commonly used for large-scale storage and data centers.
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Btrfs: A modern file system that is designed to be robust and scalable, and includes features like copy-on-write, snapshots, and more.
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NTFS: A file system that is used by Windows, but can also be read and written by Linux systems.
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FAT32: A file system that is commonly used for removable storage devices like USB drives and SD cards.
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ReiserFS: another alternative filesystem, which was considered a fast filesystem and extensively used in many distributions.
These are just a few examples of file system types that can be used in Linux systems.
Conclusion
Linux supports a wide range of file system types, each with its own strengths and uses cases. The extended file system (ext) is the most widely used file system for Linux systems and is well-suited for most everyday use cases. For large-scale storage and data centers, XFS is a high-performance option. Btrfs is a modern file system that is designed to be robust and scalable and includes advanced features like copy-on-write, snapshots, and more. NTFS and FAT32 are file systems that are commonly used by Windows but can also be read and written by Linux systems. ReiserFS is another alternative file system, which was considered as a fast file system and was extensively used in many distributions. Depending on the specific needs and requirements of a Linux system, the appropriate file system type can be chosen to optimize performance and reliability.