anitsh
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4 years ago Filesystem Hierarchy Standard (FHS)
The Filesystem Hierarchy Standard defines the directory structure and directory contents in Linux distributions. It is maintained by the Linux Foundation.
To comply with the FSSTND the following directories, or symbolic links to directories, are required in root directory where Linux file system starts.
/ The root directory.
/bin Essential command binaries
/boot Static files of the boot loader
/dev Device files
/etc Host-specific system configuration
/lib Essential shared libraries and kernel modules
/media Mount point for removeable media
/mnt Mount point for mounting a filesystem temporarily
/opt Add-on application software packages
/sbin Essential system binaries
/srv Data for services provided by this system
/tmp Temporary files
/usr Secondary hierarchy
/var Variable data
Everything is a file in LinuxLinux views all file systems from the perspective of a common set of objects.Filesystem
A file system or filesystem (often abbreviated to fs) controls how data is stored and retrieved. Without a file system, data placed in a storage medium would be one large body of data with no way to tell where one piece of data stops and the next begins. By separating the data into pieces and giving each piece a name, the data is easily isolated and identified. Taking its name from the way paper-based data management system is named, each group of data is called a "file." The structure and logic rules used to manage the groups of data and their names is called a "file system."
There are many different kinds of file systems. Each one has different structure and logic, properties of speed, flexibility, security, size and more. Some file systems have been designed to be used for specific applications.
File systems can be used on numerous different types of storage devices that use different kinds of media. As of 2019, hard disk drives have been key storage devices and are projected to remain so for the foreseeable future. Other kinds of media that are used include SSDs, magnetic tapes, and optical discs. In some cases, such as with tmpfs, the computer's main memory (random-access memory, RAM) is used to create a temporary file system for short-term use.
Some file systems are used on local data storage devices; others provide file access via a network protocol (for example, NFS, SMB, or 9P clients). Some file systems are "virtual", meaning that the supplied "files" (called virtual files) are computed on request (such as procfs and sysfs) or are merely a mapping into a different file system used as a backing store. The file system manages access to both the content of files and the metadata about those files. It is responsible for arranging storage space; reliability, efficiency, and tuning with regard to the physical storage medium are important design considerations.
Filesystem Hierarchy Standard (FHS)
The Filesystem Hierarchy Standard (FHS) defines the directory structure and directory contents in Linux distributions. It is maintained by the Linux Foundation.
Virtual Filesystem
The Linux kernel requires that for an entity to be a filesystem, it must also implement the open(), read(), and write() methods on persistent objects that have names associated with them. From the point of view of object-oriented programming, the kernel treats the generic filesystem as an abstract interface, and these big-three functions are "virtual," with no default definition. Accordingly, the kernel's default filesystem implementation is called a virtual filesystem (VFS).
Resource
The Linux 5.10 release included a change that is expected to significantly increase the performance of the ext4 filesystem; it goes by the name "fast commits" and introduces a new, lighter-weight journaling method. Let us look into how the feature works, who can benefit from it, and when its use may be appropriate.Ext4 is a journaling filesystem.
https://en.wikipedia.org/wiki/Journaling_file_system A journaling file system is a file system that keeps track of changes not yet committed to the file system's main part by recording the intentions of such changes in a data structure known as a "journal", which is usually a circular log. In the event of a system crash or power failure, such file systems can be brought back online more quickly with a lower likelihood of becoming corrupted. Depending on the actual implementation, a journaling file system may only keep track of stored metadata, resulting in improved performance at the expense of increased possibility for data corruption. Alternatively, a journaling file system may track both stored data and related metadata, while some implementations allow selectable behavior in this regard.