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Distributed File Systems File Systems Distributed File Systems Distributed File Systems Tran Giang Son, [email protected] ICT Department, USTH Distributed File Systems Tran Giang Son, [email protected] 1 / 40 File Systems Distributed File Systems File Systems Distributed File Systems Tran Giang Son, [email protected] 2 / 40 • System that permanently stores data • Layered on top of a lower-level physical storage medium • Divided into logical units called “files” • Files ∈ directories • Directories ∈ volume • Directories ∈ directories • Addressable with “Path” File Systems Distributed File Systems File Systems Distributed File Systems Tran Giang Son, [email protected] 3 / 40 File Systems Distributed File Systems File Systems • System that permanently stores data • Layered on top of a lower-level physical storage medium • Divided into logical units called “files” • Files ∈ directories • Directories ∈ volume • Directories ∈ directories • Addressable with “Path” Distributed File Systems Tran Giang Son, [email protected] 3 / 40 • File • Name • Owner / group • Date • Last access date • ... File Systems Distributed File Systems Metadata • Volume • Available space • Formatting info • Character set • ... Distributed File Systems Tran Giang Son, [email protected] 4 / 40 File Systems Distributed File Systems Metadata • Volume • Available space • Formatting info • Character set • ... • File • Name • Owner / group • Date • Last access date • ... Distributed File Systems Tran Giang Son, [email protected] 4 / 40 File Systems Distributed File Systems Virtual File System • / • Nested directories • Symlinks • Mount points Distributed File Systems Tran Giang Son, [email protected] 5 / 40 File Systems Distributed File Systems Low Level Organization • File data and metadata stored separately • File descriptors + meta-data stored in inodes • Large tree or tables • File content lookups • Replicable Distributed File Systems Tran Giang Son, [email protected] 6 / 40 File Systems Distributed File Systems Low Level Organization • Disks: /dev/sdX (Linux) or /dev/diskX (macOS) • Sequential array of blocks • 1KB chunks • Tree structure is flattened into blocks • Fragmentation Distributed File Systems Tran Giang Son, [email protected] 7 / 40 File Systems Distributed File Systems Fragmentation A B C (free space) A B C A (free space) A (free space) C A (free space) A D C A D (free) Distributed File Systems Tran Giang Son, [email protected] 8 / 40 ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: Distributed File Systems Tran Giang Son, [email protected] 9 / 40 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 Distributed File Systems Tran Giang Son, [email protected] 9 / 40 zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs Distributed File Systems Tran Giang Son, [email protected] 9 / 40 ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs Distributed File Systems Tran Giang Son, [email protected] 9 / 40 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 Distributed File Systems Tran Giang Son, [email protected] 9 / 40 MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS Distributed File Systems Tran Giang Son, [email protected] 9 / 40 UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS Distributed File Systems Tran Giang Son, [email protected] 9 / 40 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 Distributed File Systems Tran Giang Son, [email protected] 9 / 40 ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS Distributed File Systems Tran Giang Son, [email protected] 9 / 40 SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS Distributed File Systems Tran Giang Son, [email protected] 9 / 40 • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS Distributed File Systems Tran Giang Son, [email protected] 9 / 40 HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: Distributed File Systems Tran Giang Son, [email protected] 9 / 40 HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS Distributed File Systems Tran Giang Son, [email protected] 9 / 40 APFS • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ Distributed File Systems Tran Giang Son, [email protected] 9 / 40 • DOS/Windows: FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS Distributed File Systems Tran Giang Son, [email protected] 9 / 40 FAT FAT16 FAT32 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: Distributed File Systems Tran Giang Son, [email protected] 9 / 40 NTFS • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive • Some has encryption supports: APFS HFS+ btrfs ZFS ext4 File Systems Distributed File Systems Local File System • Very numerous • Unix-like systems: ext2/3/4 btrfs zfs ReiserFS Reiser4 JFS MinixFS UFS UFS2 XFS ZFS SquashFS • macOS: HFS HFS+ APFS • DOS/Windows: FAT FAT16 FAT32 Distributed File Systems Tran Giang Son, [email protected] 9 / 40 • Flash devices: JFFS JFFS2 exFAT • Case (in)sensitive
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