File Systems
Everything on SkillVeris tagged File Systems — collected across the glossary, study notes, blog, and cheat sheets.
15 resources across 1 library
Interview Questions(15)
What is an Inode and What Does It Store?
An inode is a fixed-size metadata record that a Unix-style file system keeps for every file, storing ownership, permissions, timestamps, size, and pointers to…
What is the FAT File System and How Does It Work?
FAT (File Allocation Table) is a simple, flat file system that tracks which disk clusters belong to a file using a single shared table of linked-list-style ent…
What is NTFS and How Does It Improve on FAT?
NTFS (New Technology File System) is Windows' journaling file system that stores nearly all metadata — including tiny files themselves — as records in a Master…
What is ext4 and What Improvements Does It Bring?
ext4 is the default Linux file system that improves on ext3 by using extents instead of pure block-mapping for large files, adding delayed allocation and multi…
What is Journaling in a File System and Why Does It Matter?
Journaling is a technique where a file system writes a record of an intended metadata (and optionally data) change to a dedicated log before applying that chan…
What are File Allocation Methods in an OS?
File allocation methods are the strategies a file system uses to map a file’s logical blocks onto physical disk blocks, and the three classic approaches are co…
What are Directory Structure Types in an OS?
Directory structure types describe how a file system organizes the mapping from file names to files, and the main forms are single-level, two-level, tree-struc…
What is File System Consistency Checking (fsck)?
File system consistency checking is the process of scanning on-disk metadata — inodes, directory entries, block bitmaps, and free lists — after an unclean shut…
What is a Log-Structured File System?
A log-structured file system treats the entire disk as a single sequential append-only log, buffering all writes — data and metadata alike — into large segment…
What is NFS (Network File System)?
NFS (Network File System) is a protocol that lets a client machine mount a directory exported by a remote server and access its files using the same system cal…
What is the Virtual File System (VFS) Layer?
The Virtual File System (VFS) layer is an abstraction inside the kernel that defines a common set of file operations — open, read, write, close, and more — so…
What is a File Descriptor Table?
A file descriptor table is a per-process array maintained by the kernel that maps small integers (file descriptors), which a process uses in system calls, to e…
What is the Open File Table?
The open file table is a kernel-wide (system-wide) structure of entries, each tracking the current file offset, access mode, and status flags for one open() ca…
What is the Buffer Cache in an Operating System?
The buffer cache is a region of kernel memory that holds recently used raw disk blocks so that repeated reads and writes to the same block hit fast RAM instead…
Page Cache vs Buffer Cache: What Is the Difference?
The page cache caches file contents in memory indexed by file and byte offset (used for regular file reads, writes, and mmap()), while the buffer cache histori…