Comparison of file systems

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The following tables compare general and technical information for a number of file systems.

General information[edit]

File system Creator Year
introduced
Original operating system License
DECtape DEC 1964 PDP-6 Monitor
Level-D DEC 1968 TOPS-10
George 2 ICT (later ICL) 1968 George 2
ODS-1 DEC 1972 RSX-11
RT-11 file system DEC 1973 RT-11
DOS (GEC) GEC 1973 Core Operating System
CP/M file system Gary Kildall 1974 CP/M
V6FS Bell Labs 1975 Version 6 Unix
OS4000 GEC 1977 OS4000
FAT (8-bit) Marc McDonald, Microsoft 1977 Microsoft Stand-alone Disk BASIC-80
DOS 3.x Apple Computer 1978 Apple DOS
Pascal Apple Computer 1978 Apple Pascal
CBM DOS Commodore 1978 Microsoft BASIC (for CBM PET)
V7FS Bell Labs 1979 Version 7 Unix
ODS-2 DEC 1979 OpenVMS
FAT12 Tim Paterson, Seattle Computer Products 1980 QDOS, 86-DOS
AFS Carnegie Mellon University 1982 Multiplatform MultoOS
DFS Acorn Computers Ltd 1982 Acorn BBC Micro MOS
ADFS Acorn Computers Ltd 1983 Acorn Electron (later Arthur RISC OS)
FFS Kirk McKusick 1983 4.2BSD
ProDOS Apple Computer 1983 ProDOS 8
MFS Apple Computer 1984 Mac OS
FAT16 Microsoft, IBM 1984 PC DOS 3.0/MS-DOS 3.0
Elektronika BK tape format NPO "Scientific centre" (now Sitronics) 1985 Vilnius Basic, BK monitor program
HFS Apple Computer 1985 Mac OS
Amiga OFS[16] Metacomco for Commodore 1985 Amiga OS
High Sierra Ecma International 1985 MS-DOS, Mac OS
NWFS Novell 1985 NetWare 286
FAT16B Compaq 1987 Compaq MS-DOS 3.31, DR DOS 3.31
MINIX V1 FS Andrew S. Tanenbaum 1987 MINIX 1.0
Amiga FFS Commodore 1988 Amiga OS 1.3
HPFS IBM & Microsoft 1988 OS/2
ISO 9660:1988 Ecma International, Microsoft 1988 MS-DOS, Mac OS, and AmigaOS
JFS1 IBM 1990 AIX[1]
VxFS VERITAS, (now Symantec) 1991 developed for Unix System Laboratories, HP-UX[2]
ext Rémy Card 1992 Linux
WAFL NetApp 1992 Data ONTAP
MINIX V2 FS Andrew S. Tanenbaum 1992 MINIX 1.6 and 2.0
AdvFS DEC 1993[3] Digital Unix
NTFS Version 1.0 Microsoft, Tom Miller, Gary Kimura 1993 Windows NT 3.1 proprietary
LFS Margo Seltzer 1993 Berkeley Sprite
ext2 Rémy Card 1993 Linux, Hurd
UFS1 Kirk McKusick 1994 4.4BSD
XFS SGI 1994 IRIX
HFS (Hierarchical File System) IBM 1994 MVS/ESA (now z/OS)
Rock Ridge Young Minds Inc. 1994 Linux, Mac OS, Amiga OS, and FreeBSD
Joliet ("CDFS") Microsoft 1995 Microsoft Windows, Linux, Mac OS, and FreeBSD
PFS Michiel Pelt 1996 AmigaOS
Romeo Adaptec 1996 Microsoft Windows
UDF ISO/ECMA/OSTA 1995 -
FAT32 Microsoft 1996 Windows 95b[4]
QFS LSC Inc, Sun Microsystems 1996 Solaris
GPFS IBM 1996 AIX, Linux, Windows
Be File System Be Inc., D. Giampaolo, C. Meurillon 1996 BeOS
HFS Plus Apple Computer 1998 Mac OS 8.1
NSS Novell 1998 NetWare 5
PolyServe File System (PSFS) PolyServe 1998 Windows, Linux
ODS-5 DEC 1998 OpenVMS 7.2
SFS John Hendrikx 1998 AmigaOS, AROS, MorphOS
ext3 Stephen Tweedie 1999 Linux
ISO 9660:1999 Ecma International, Microsoft 1999 Microsoft Windows, Linux, Mac OS X, FreeBSD, and AmigaOS
JFS IBM 1999 OS/2 Warp Server for e-business
GFS Sistina (Red Hat) 2000 Linux
Melio FS Sanbolic 2001 Windows
NTFS Version 3.1 Microsoft 2001 Windows XP proprietary
ReiserFS Namesys 2001 Linux
zFS IBM 2001 z/OS (backported to OS/390)
FATX Microsoft 2002 Xbox
UFS2 Kirk McKusick 2002 FreeBSD 5.0
Lustre Cluster File Systems (later Oracle Corporation) 2002 Linux
OCFS Oracle Corporation 2002 Linux
VMFS2 VMware 2002 VMware ESX Server 2.0
ext3cow Zachary Peterson 2003 Linux
Fossil Bell Labs 2003 Plan 9 from Bell Labs 4
Google File System Google 2003 Linux
PramFS MontaVista 2003 Linux
Reliance[5] Datalight 2003 Windows CE, VxWorks, custom ports
VxCFS VERITAS, (now Symantec) 2004 AIX, HP-UX, Solaris, Linux
ZFS Sun Microsystems 2004 Solaris CDDL
Reiser4 Namesys 2004 Linux
Non-Volatile File System Palm, Inc. 2004 Palm OS Garnet
MINIX V3 FS Andrew S. Tanenbaum 2005 MINIX 3
OCFS2 Oracle Corporation 2005 Linux
NILFS NTT 2005 Linux
VMFS3 VMware 2005 VMware ESX Server 3.0
GFS2 Red Hat 2006 Linux
ext4 Various 2006 Linux
exFAT Microsoft 2006, 2009 Windows CE 6.0, Windows XP SP3, Windows Vista SP1 proprietary
TexFAT/TFAT Microsoft 2006 Windows CE 6.0
Btrfs Oracle Corporation 2007 Linux GPL
Ceph Sage Weil, Inktank Storage 2007, 2012 Linux
WBFS kwiirk and Waninkoko (Wii homebrew) 2008 Nintendo WII
HAMMER Matthew Dillon 2008 DragonFly BSD
Tux3 Various 2008 Linux
UBIFS Nokia with help of University of Szeged 2008 Linux
Oracle ACFS Oracle Corporation 2009 Linux - Red Hat Enterprise Linux 5 and Oracle Enterprise Linux 5 only
Reliance Nitro[5] Datalight 2009 Windows CE, Windows Mobile, VxWorks, Linux, custom ports
LTFS IBM 2010 Linux, Mac OS X, planned Microsoft Windows, LGPL
IlesfayFS Ilesfay Technology Group 2011 Microsoft Windows, planned Red Hat Enterprise Linux
VMFS5 VMware 2011 VMware ESXi 5.0tux 3 stats
ReFS Microsoft 2012, 2013 Windows 2012 Server
Lanyard Filesystem Dan Luedtke 2012 Linux
F2FS Samsung 2012 Linux GPLv2
File system Creator Year
introduced
Original operating system License

Limits[edit]

File system Maximum filename length Allowable characters in directory entries[6] Maximum pathname length Maximum file size Maximum volume size[7]
Acorn ADFS 10 bytes Any ISO 8859-1 character except: SPACE $ & % @ \ ^ : . # * " ¦ No limit defined 512 MB or 4 GB[8] 512 MB or 4 GB[9]
AdvFS 226 characters Any byte except NUL[10] No limit defined[11] 16 TB 16 TB
Apple DOS 3.x 30 bytes Any byte except NUL 30 B, no subdirectories (105 files per disk) Unknown 140 kB DOS 3.3 (assuming standard 35 tracks)
113.75 kB DOS 3.1, 3.2
Apple ProDOS 15 bytes A-Z, a-z, 0-9, and period 64 B, including slashes[12][13] 16 MB 32 MB
BFS 255 bytes Any byte except NUL[10] No limit defined[11] 260 GB[14] 2 EB
Btrfs 255 bytes Any byte except NUL Unknown 16 EB 16 EB
CBM DOS 16 bytes Any byte except NUL Non-hierarchical 16 MB 16 MB
CP/M file system 8.3 any byte except: SPACE < > . , ; : = ? * [ ] % | ( ) / \[15] 16 "user areas", no subdirectories 8 MB[16] 8 MB to 512 MB[16]
DECtape 6.3 A–Z, 0–9 DTxN:FILNAM.EXT = 15 369,280 B (577 * 640) 369,920 B (578 * 640)
DOS (GEC) 8 bytes A–Z, 0–9 Non-hierarchical 64 MB 64 MB
Elektronika BK tape format 16 bytes Unknown Non-hierarchical 64 kB 800 kB (approx) per side for 90 min cassette (limited only by tape length)
exFAT 255 characters[17] Any Unicode except NUL No limit defined 127 PB 64 ZB, 512 TB recommended[18]
ext2 255 bytes Any byte except NUL[10] and / No limit defined[11] 2 TB[7] 32 TB
ext3 255 bytes Any byte except NUL[10] and / No limit defined[11] 2 TB[7] 32 TB
ext3cow 255 bytes Any byte except NUL,[10] / and @ No limit defined[11] 2 TB[7] 32 TB
ext4 255 bytes Any byte except NUL[10] and / No limit defined[11] 16 TB[7][19] 1 EB[20]
TexFAT 247 characters Any Unicode except NUL No limit defined 2 GB 500 GB Tested[21]
F2FS 255 bytes Unknown Unknown 3.94 TB 16 TB
FAT12 8.3 (255 UTF-16 code units with LFN)[22] Any byte except for values 0-31, 127 (DEL) and: " * / : < > ? \ | + , . ; = [] (lowcase a-z are stored as A-Z). With VFAT LFN any Unicode except NUL[22][10] No limit defined[11] 32 MB (256 MB) 32 MB (256 MB)
FAT16 8.3 (255 UTF-16 code units with LFN)[22] Any byte except for values 0-31, 127 (DEL) and: " * / : < > ? \ | + , . ; = [] (lowcase a-z are stored as A-Z). With VFAT LFN any Unicode except NUL[22][10] No limit defined[11] 2 GB (4 GB) 2 GB or 4 GB
FAT32 8.3 (255 UTF-16 code units with LFN)[22] Any byte except for values 0-31, 127 (DEL) and: " * / : < > ? \ | + , . ; = [] (lowcase a-z are stored as A-Z). With VFAT LFN any Unicode except NUL[22][10] No limit defined[11] 4 GB (256 GB[23]) 2 TB[24] (16 TB)
FATX 42 bytes[22] ASCII. Unicode not permitted. No limit defined[11] 2 GB 2 GB
FFS 255 bytes Any byte except NUL[10] No limit defined[11] 8 ZB 8 ZB
Fossil Unknown Unknown Unknown Unknown Unknown
GFS 255 Any byte except NUL[10] No limit defined[11] 8 EB[25] 8 EB[25]
GPFS 255 UTF-8 codepoints Any byte except NUL[10] No limit defined[11] 512 YB 512 YB (4 PB tested)
HAMMER Unknown Unknown Unknown Unknown 1 EB
HFS 31 bytes Any byte except :[26] Unlimited 2 GB 2 TB
HFS Plus 255 UTF-16 code units[27] Any valid Unicode[10][28] Unlimited 8 EB 8 EB[29][30]
High Sierra Unknown Unknown Unknown Unknown Unknown|-
HPFS 255 bytes Any byte except NUL[31] No limit defined[11] 2 GB 2 TB[32]
ISO 9660:1988 Level 1: 8.3,
Level 2 & 3: ~ 180
Depends on Level[33] ~ 180 bytes? 4 GB (Level 1 & 2) to 8 TB (Level 3)[34] 8 TB[35]
ISO 9660:1999 Unknown Unknown Unknown Unknown Unknown
Joliet ("CDFS") 64 Unicode characters All UCS-2 code except * / \ : ; and ?[36] Unknown 4 GB (same as ISO 9660:1988) 8 TB (same as ISO 9660:1988)
Lanyard Filesystem 255 bytes Any byte except NUL and /[10] No limit defined 64 ZB 128 kB to 64 ZB[37]
LEAN 4,068 bytes[38] case sensitive, in UTF-8 (any Unicode codepoint) No limit defined 8 EB 8 EB
Level-D 6.3 A–Z, 0–9 DEVICE:FILNAM.EXT[PROJECT,PROGRM] = 7 + 10 + 15 = 32; + 5*7 for SFDs = 67 24 GB (34,359,738,368 words (235-1); 206,158,430,208 SIXBIT bytes) 12 GB (approx; 64 * 178 MB)
LTFS Unknown Unknown Unknown Unknown Unknown
Lustre 255 bytes Any byte except NUL[10] and / No limit defined[11] 32 PB (on ext4) 1 YB (55 PB tested)
JFS1 255 bytes Any byte except NUL[10] No limit defined[11] 8 EB 4 PB
JFS 255 bytes Any Unicode except NUL No limit defined[11] 4 PB 32 PB
MFS 255 bytes Any byte except : No path (flat filesystem) 226 MB 226 MB
MicroDOS file system 14 bytes Unknown Unknown 16 MB 32 MB
MINIX V1 FS 14 or 30 bytes, set at filesystem creation time Any byte except NUL[10] No limit defined[11] 64 MB[39] 64 MB[39]
MINIX V2 FS 14 or 30 bytes, set at filesystem creation time Any byte except NUL[10] No limit defined[11] 4 GB[39] 1 GB, then 2 TB[39]
MINIX V3 FS 60 bytes Any byte except NUL[10] No limit defined[11] 4 GB 16 TB[39]
NILFS 255 bytes Any byte except NUL[10] No limit defined[11] 8 EB 8 EB
NSS 226 characters Depends on namespace used[40] Only limited by client 8 TB 8 TB
NTFS 255 characters[41][42][43] Depends on namespace used[41][42][43][44] 32,767 Unicode characters with each path component (directory or filename) commonly up to 255 characters long[11] 16 EB[45] 16 EB[45]
NWFS 80 bytes[46] Depends on namespace used[40] No limit defined[11] 4 GB 1 TB
OCFS 255 bytes Any byte except NUL[10] No limit defined[11] 8 TB 8 TB
OCFS2 255 bytes Any byte except NUL[10] No limit defined[11] 4 PB 4 PB
ODS-5 236 bytes[47] Unknown 4,096 bytes[48] 2 TB 2 TB
OS4000 8 bytes A–Z, 0–9
Period is directory separator
No limit defined[11] 2 GB 1 GB (at least)
PramFS 31 bytes Any byte except NUL Unknown 1 GB 8 EB
QFS 255 bytes Any byte except NUL[10] No limit defined[11] 16 EB[49] 4 PB[49]
ReFS 32,767 Unicode characters (255 Unicode characters in Windows 8/8.1)[50] Unknown 32,767 Unicode characters in each path component 16 EB 1 YB with 64 kB cluster size (264 × 64 × 210). Windows stack addressing allows 16 EB
ReiserFS 4,032 bytes/226 characters Any byte except NUL[10] No limit defined[11] 8 TB[51] (v3.6), 2 GB (v3.5) 16 TB
Reiser4 3,976 bytes Any byte except / and NUL No limit defined[11] 8 TB on x86 Unknown
Reliance 260 bytes OS specific 260 B 4 GB 2 TB
Reliance Nitro 1,024 bytes OS specific 1024 bytes 32 TB 32 TB
RT-11 6.3 A–Z, 0–9, $ Non-hierarchical 32 MB (65536 * 512) 32 MB
IBM SFS 8.8 Unknown Non-hierarchical[52] Unknown Unknown
UDF 255 bytes Any Unicode except NUL 1,023 bytes[53] 16 EB 2 TB (hard disk), 8 TB (optical disc)[54]
UFS1 255 bytes Any byte except NUL[10] No limit defined[11] 226 TB 226 TB
UFS2 255 bytes Any byte except NUL[10] No limit defined[11] 32 PB 1 YB
V6FS 14 bytes[55] Any byte except NUL and /[10] No limit defined[11] 16 MB[56] 2 TB
V7FS 14 bytes[57] Any byte except NUL and /[10] No limit defined[11] 1 GB[58] 2 TB
VxFS 255 bytes Any byte except NUL[10] No limit defined[11] 256 TB 256 TB
VMFS2 128 Any byte except NUL and /[10] 2,048 4 TB[59] 64 TB
VMFS3 128 Any byte except NUL and /[10] 2,048 2 TB[59] 64 TB
XFS 255 bytes[60] Any byte except NUL[10] No limit defined[11] 8 EB[61] 8 EB[61]
ZFS 255 bytes Any Unicode except NUL No limit defined[11] 16 EB 256 ZB
File system Maximum filename length Allowable characters in directory entries[6] Maximum pathname length Maximum file size Maximum volume size[7]

Metadata[edit]

File system Stores file owner POSIX file permissions Creation timestamps Last access/ read timestamps Last content modification timestamps Disk copy created Last metadata change timestamps Last archive timestamps Access control lists Security/ MAC labels Extended attributes/ Alternate data streams/ forks Checksum/ ECC Max Timestamp Resolution
AdvFS Yes Yes No Yes Yes Unknown Yes No Yes No Yes No Unknown
Be File System Yes Yes Yes No Unknown Unknown No No No No Yes No Unknown
Btrfs Yes Yes Yes Yes Yes Unknown Yes Unknown Yes Yes Yes Yes 1 nanosecond
CBM DOS No No No No No No No No No No No No Unknown
CP/M file system No No Yes[62] No Unknown Unknown No No No No No No Unknown
DECtape No No Yes No Unknown Unknown No No No No No No Unknown
DOS (GEC) Yes No Yes Yes Yes Unknown No No No No No No Unknown
Elektronika BK tape format No No No No Unknown Unknown No No No No No Yes Unknown
ext2 Yes Yes No Yes Yes Unknown Yes No Yes[63] Yes[63] Yes No 1 second
ext3 Yes Yes No Yes Yes No Yes No Yes[63] Yes[63] Yes No 1 second
ext3cow Yes Yes No Yes Yes No Yes No Yes[63] Yes[63] Yes No 1 second
ext4 Yes Yes Yes Yes Yes Unknown Yes No Yes[63] Yes[63] Yes Partial[64] 1 nanosecond
exFAT No No Yes Yes Yes No Unknown No No Unknown Unknown Partial 10 milliseconds
FAT12 No[65] No[66] Partial[67] Partial[67] Yes Yes No[68] No No No No[69] No 10 milliseconds
FAT16 No[65] No[66] Partial[67] Partial[67] Yes Yes No[68] No No No No[69] No 10 milliseconds
FAT32 No No Partial[67] Partial[67] Yes Yes No[68] No No No No No 10 milliseconds
FFS Yes Yes No Yes Yes Unknown Yes No No No No No Unknown
Fossil Yes Yes[70] No Yes Unknown Unknown Yes No No No No No Unknown
GPFS Yes Yes Yes Yes Yes Unknown Yes No Yes Yes Yes Yes Unknown
GFS Yes Yes No Yes Unknown Unknown Yes No Yes[63] Yes[63] Yes No Unknown
HFS No No Yes No Yes No No Yes No No Yes No Unknown
HFS Plus Yes Yes Yes Yes Yes No Yes Yes Yes Yes[71] Yes No 1 second
HPFS Yes[72] No Yes Yes Yes Unknown No No No Unknown Yes No Unknown
High Sierra No No Yes No Unknown Unknown No No No No No No Unknown
ISO 9660:1988 No No Yes[73] No[74] Yes[75] Unknown No No No No No No Unknown
ISO 9660:1999 No No Yes No Unknown Unknown No No No No No No Unknown
JFS Yes Yes Yes Yes Yes Unknown Yes No Yes Yes Yes No 1 second
Joliet ("CDFS") No No Yes[73] No[74] Yes[75] Unknown No No No No No No Unknown
Lanyard Filesystem No No Yes No Yes No Yes No No No No No 1 nanosecond
Level-D Yes Yes Yes Yes Unknown Unknown Yes Yes Yes No No No Unknown
LFS Yes Yes No Yes Yes Unknown Yes No No No No No Unknown
Lustre Yes Yes Partial[76] Yes Yes No Yes No Yes Yes Yes Partial[77][78] Unknown
NILFS Yes Yes Yes No Unknown Unknown Yes No Planned No Planned Yes Unknown
NTFS Yes Yes[79] Yes Yes Yes No Yes No Yes Yes[80] Yes No 100 nanoseconds
NSS Yes Yes Yes[81] Yes[81] Unknown Unknown Yes Yes[81] Yes Unknown Yes[82][83] No Unknown
NWFS Yes Unknown Yes[81] Yes[81] Unknown Unknown Yes Yes[81] Yes Unknown Yes[82][83] No Unknown
OCFS No Yes No No Unknown Unknown Yes Yes No No No No Unknown
OCFS2 Yes Yes No Yes Unknown Unknown Yes No Yes No Yes Partial[84] Unknown
ODS-5 Yes Yes Yes Unknown Unknown Unknown Unknown Yes Yes Unknown Yes[85] No Unknown
OS4000 Yes No Yes Yes Yes Unknown No No No No No No Unknown
PramFS Yes Yes No Yes Yes Unknown Yes No Yes Yes Yes Yes 1 second
QFS Yes Yes Yes Yes Unknown Unknown Yes Yes Yes No Yes No Unknown
ReiserFS Yes Yes No Yes Yes No No No No No No No Unknown
Reiser4 Yes Yes No Yes Yes Unknown Yes No No No No No Unknown
Reliance No No Yes No Yes No No No No No No Partial[86] Unknown
Reliance Nitro Linux port Linux port Yes Yes Yes No No No Linux port No Yes Partial[86] Unknown
UDF Yes Yes Yes Yes Unknown Unknown Yes Yes Yes No Yes No Unknown
UFS1 Yes Yes No Yes Yes Unknown Yes No Yes[87] Yes[87] No[88] No Unknown
UFS2 Yes Yes Yes Yes Yes Unknown Yes No Yes[87] Yes[87] Yes No Unknown
V6FS Yes Yes No Yes Yes Unknown Yes No No No No No Unknown
V7FS Yes Yes No Yes Yes Unknown Yes No No No No No Unknown
VMFS2 Yes Yes No Yes Unknown Unknown Yes No No No No No Unknown
VMFS3 Yes Yes No Yes Unknown Unknown Yes No No No No No Unknown
VxFS Yes Yes Yes Yes Yes Unknown Yes No Yes Unknown Yes[63] No Unknown
XFS Yes Yes No Yes Yes Unknown Yes No Yes Yes[63] Yes Partial 1 nanosecond
ZFS Yes Yes Yes Yes Yes Unknown Yes Yes Yes Yes[89] Yes[90] Yes 1 nanosecond
File system Stores file owner POSIX file permissions Creation timestamps Last access/read timestamps Last content modification timestamps Disk copy created Last metadata change timestamps Last archive timestamps Access control lists Security/ MAC labels Extended attributes/ Alternate data streams/ forks Checksum/ ECC Max Timestamp Resolution

Features[edit]

File system Hard links Symbolic links Block journaling Metadata-only journaling Case-sensitive Case-preserving File Change Log Snapshot XIP Encryption COW Integrated LVM Data deduplication Volumes are resizeable
Be File System No Yes No Yes Yes Yes Unknown No No No No No No Unknown
Btrfs Yes Yes No No Yes Yes Yes Yes No Planned[91] Yes Yes Yes (via bedup)[92] Online
CBM DOS No No No No Yes Yes No No No No No No No No
CP/M file system No No No No No No No No No No No No No Unknown
DECtape No No No No No No No No No No No No No Unknown
DOS (GEC) No No No No No No No No No No No No No Unknown
ext2 Yes Yes No No Yes Yes No No Yes[93] No No No No Online[94]
ext3 Yes Yes Yes[95] Yes Yes Yes No No Yes Yes[citation needed] No No No Online[94]
ext3cow Yes Yes Yes[95] Yes Yes Yes Unknown Yes Unknown Yes Yes No No Unknown
ext4 Yes Yes Yes[95] Yes Yes Yes No No Yes Yes[citation needed] No No No Online[94]
exFAT No No No No No Yes No Unknown Unknown No Unknown Unknown Unknown Unknown
FAT12 No No No No No Partial No No No No No No No Offline[96]
FAT16 No No No No No Partial No No No No No No No Offline[96]
FAT32 No No No No No Partial No No No No No No No Offline[96]
FFS Yes Yes No No[97] Yes Yes No No No No No No No Offline (cannot be shrunk)[98]
Fossil No No No No Yes Yes Yes Yes No No Unknown No Yes[99] Unknown
GFS Yes Yes[100] Yes Yes[101] Yes Yes No No No No Unknown Unknown Unknown Online
GPFS Yes Yes Unknown Unknown Yes Yes Yes Yes Yes No Yes Yes No Online
HAMMER Yes Yes Unknown Unknown Yes Yes Unknown Yes Unknown Unknown Unknown Unknown On demand Unknown
HFS No Yes[102] No No No Yes No No No No No No No Unknown
HFS Plus Yes[103] Yes No Yes[104] Partial[105] Yes Yes[106] No No Yes[107] No No No Yes[108]
HPFS No No No No No Yes No Unknown No No Unknown Unknown No Unknown
JFS Yes Yes No Yes Yes[109] Yes No Yes No No No Unknown Unknown Online (cannot be shrunk)[110]
Lanyard Filesystem No No No No Yes Yes No No No No No No No Offline (cannot be shrunk)
Level-D No No No No No No No No No No Unknown Unknown Unknown Unknown
LFS Yes Yes Yes[111] No Yes Yes No No No No Unknown Unknown Unknown Unknown
Lustre Yes Yes Yes[95] Yes Yes Yes Yes in 2.0 and later No[78] No No No[78] No[78] No[78] Online[112]
NILFS Yes Yes Yes[111] No Yes Yes Yes Yes No No Yes Unknown Unknown Online (since Linux-3.x and nilfs-utils 2.1)
NSS Yes Yes Unknown Yes Yes[113] Yes[113] Yes[114] Yes No Yes Unknown Unknown Unknown Unknown
NTFS Yes Yes[115] No[116] Yes[116] Yes[117] Yes Yes Partial[118] Yes Yes Partial Unknown Yes (Windows Server 2012)[119] Online[120]
NWFS Yes[121] Yes[121] No No Yes[113] Yes[113] Yes[114] Unknown No No No Yes[122] Unknown Unknown
OCFS No Yes No No Yes Yes No No No No Unknown Unknown Unknown Unknown
OCFS2 Yes Yes Yes Yes Yes Yes No Partial[123] No No Unknown No No Online for version 1.4 and higher
ODS-2 Yes Yes[124] No Yes No No Yes Yes No No Unknown Unknown Unknown Unknown
ODS-5 Yes Yes[124] No Yes No Yes Yes Yes Unknown No Unknown Unknown Unknown Unknown
OS4000 No Yes[125] No No No No No No No No No No No Unknown
PramFS No Yes No No Yes Yes No No Yes No No No No No
QFS Yes Yes No Yes Yes Yes No No No No Unknown Unknown Unknown Unknown
ReiserFS Yes Yes No[126] Yes Yes Yes No No No No No No No Online
Reiser4 Yes Yes Yes No Yes Yes No Unknown No Yes[127] Yes No Unknown Online (can only be shrunk offline)
Reliance No No No[128] No No Yes No No No No Yes No No Unknown
Reliance Nitro Yes Yes No[128] No Depends on OS Yes No No No No Yes No No Unknown
RT-11 No No No No No No No No No No No No No Unknown
UDF Yes Yes Yes[111] Yes[111] Yes Yes No No Yes No No No No Unknown
UFS1 Yes Yes No No Yes Yes No No No No No No No Unknown
UFS2 Yes Yes No No[129][130][131] Yes Yes No Yes Unknown No No No No Offline (cannot be shrunk)[132]
V6FS Yes No No No Yes Yes No No No No No No No Unknown
V7FS Yes No[133] No No Yes Yes No No No No No No No Unknown
VxFS Yes Yes Yes No Yes Yes Yes Yes[134] Unknown No Unknown Unknown Yes Unknown
VMFS2 Yes Yes No Yes Yes Yes No No No No Unknown Unknown Unknown Unknown
VMFS3 Yes Yes No Yes Yes Yes No No No No Unknown Unknown Unknown Unknown
XFS Yes Yes Yes Yes Yes[135] Yes No No No No No No No Online (cannot be shrunk)
ZFS Yes Yes Yes[136] No[136] Yes Yes No Yes No Yes Yes Yes Yes Online (cannot be shrunk)[137]
File system Hard links Symbolic links Block journaling Metadata-only journaling Case-sensitive Case-preserving File Change Log Snapshotting XIP Encryption COW integrated LVM Data deduplication Volumes are resizeable

Allocation and layout policies[edit]

File system Block suballocation Variable file block size[138] Extents Allocate-on-flush Sparse files Transparent compression
Be File System No No Yes No Unknown No
Btrfs Partial[139] No Yes Yes Yes Yes
CBM DOS No Partial[140] No No No No
CP/M filesystem No No Yes No Yes No
DECtape No No No No No No
DOS (GEC) No Yes Yes No No No
ext2 No[141] No No No Yes No[142]
ext3 No[141] No No No Yes No
ext3cow No[141] No No No Yes No
ext4 No[141] No Yes Yes Yes No
exFAT Unknown No No Unknown No No
FAT12 No No No No No No[143]
FAT16 No No No No No No[143]
FAT32 No No No No No No
FFS 8:1[144] No No No Yes No
Fossil No No No No Unknown Yes
GFS Partial[145] No No No Yes No
HFS Plus No No Yes Yes No Yes
HPFS No No Yes No No No
JFS Yes No Yes No Yes only in JFS1 on AIX[146]
Level-D Yes No Yes No No No
LFS 8:1[144] No No No Yes No
Lustre No No Yes Yes Yes No
NSS No No Yes No Unknown Yes
NILFS No No Planned Yes Yes No
NTFS Partial No Yes No Yes Partial[147]
NWFS Yes[148] No No No Unknown Yes
OCFS No No Yes No Unknown No
OCFS2 No No Yes No Yes No
ODS-5 No No Yes No Unknown No
OS4000 No Yes Yes No No No
PramFS No No No No Yes No
QFS Yes No No No Unknown No
ReiserFS Yes No No No Yes No
Reiser4 Yes No Yes[149] Yes Yes Yes[127]
Reliance No No No No No No
Reliance Nitro No No Yes No Yes No
UDF No No Yes Depends[150] No No
UFS1 8:1[144] No No No Yes No
UFS2 8:1[144] Yes No No Yes No
V6FS No No No No Yes No
V7FS No No No No Yes No
VMFS2 Yes No No No Yes No
VMFS3 Yes No Yes No Yes No
VxFS Unknown No Yes No Yes No
XFS No No Yes Yes Yes No
ZFS Partial[151] Yes No Yes Yes Yes
File system Block suballocation Variable file block size[138] Extents Allocate-on-flush Sparse files Transparent compression

Supporting operating systems[edit]

File system DOS Windows 9x Windows NT Linux Mac OS Mac OS X FreeBSD BeOS Solaris AIX z/OS OS/2 Windows CE Windows Mobile VxWorks HP-UX Plan 9
BFS No Partial - read-only with third-party driver Partial - read-only with third-party driver Partial - read-only No Unknown No Yes Unknown Unknown Unknown Unknown No No Unknown Unknown No
Btrfs No No No Yes since kernel 2.6.29 No No No No No No No No No No Unknown Unknown No
DECtape No Unknown Unknown with AncientFS[152] No with AncientFS[152] with AncientFS[152] Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown No
exFAT No Partial read-only with third party driver Yes : Win7, Vista SP1, can be added to XP SP2 with third party driver No Yes 10.6.5+ No No Yes No No No Yes No Unknown Unknown Unknown
ext2 Unknown Unknown with Ext2Fsd (complete)[153] or Ext2 IFS (partial, no large inodes)[154] or Ext2Read (read-only, also on LVM2)[155] Yes since kernel 0.99 No with fuse-ext2,[156] ExtFS[157] and ext2fsx[158] Yes read-only Unknown Unknown Unknown third-party app[159] with 3rd-party app[160] with 3rd-party app[160] Unknown Unknown Yes
ext3 Unknown Unknown with Ext2Fsd (complete)[153] or Ext2 IFS (partial, no large inodes)[154] or Ext2Read (read-only, also on LVM2)[155] Yes since kernel 2.4.15 No with fuse-ext2[156] and ExtFS[157] Yes Unknown Yes Unknown Unknown Unknown with 3rd-party app[160] with 3rd-party app[160] Unknown Unknown No
ext3cow Unknown Unknown Unknown Yes Kernel 2.6.20 Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown No
ext4 No No Partial with Ext2Fsd (partial, extents limited)[153] or Ext2Read (read-only, also on LVM2)[155] Yes since kernel 2.6.28 No with fuse-ext2 (partial),[156] ext4fuse (read-only)[161] and ExtFS (full read/write)[157] Partial with ext4fuse (read-only)[161] Unknown Unknown Unknown Unknown Unknown No Unknown Unknown Unknown No
FAT12 Yes Yes Yes Yes Yes Yes Yes Yes No Partial on diskettes only, through dos* commands Unknown Yes Yes[162] Unknown Yes[163] Unknown Yes
FAT16 Yes since DOS 3.0, FAT16B since DOS 3.31 Yes Yes Yes Yes Yes Yes Yes Yes Partial on diskettes only, through dos* commands Unknown Yes Yes[162] Yes Yes[163] Unknown Yes
FAT32 Yes since DOS 7.1[164] Yes since Windows 95 OSR2 Yes since Windows 2000 Yes Yes Yes Yes Yes Yes Partial on diskettes only, through dos* commands Unknown with third-party app[165] Yes[162] Yes Yes[163] Unknown Yes
FFS No Unknown Unknown Yes[166] No Yes Yes Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown
Fossil No No No with 3rd-party software[167] No with 3rd-party software [167] with 3rd-party software [167] No with 3rd-party software [167] No No No No No No No Yes
GFS No Unknown Unknown Yes since kernel 2.6.19 No Unknown No Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown No
HFS No with third-party app[168] with third-party app[168][169] Yes Yes Partial: read-only since OSX 10.6[170] with third-party app[171][172] Unknown Unknown Unknown No with third-party app[173] No No No Unknown No
HFS Plus No with third-party app[168] with third-party app[168][169] Partial - write support occurs if journal is empty, but requires a force mount. Yes since Mac OS 8.1 Yes Partial read-only third-party app[174] Unknown Unknown Unknown No with third-party app No No No Unknown No
HPFS with third-party driver Partial read-only third-party driver[175] included until v3.51, third-party driver until 4.0[176] Yes No Unknown Yes Unknown Unknown Unknown Unknown Yes No Unknown Unknown Unknown No
IBM GPFS[177] No No Yes Yes since 2001 No No No No No Yes No No Unknown Unknown Unknown Unknown No
IBM HFS No No No No No No No No No No Yes No Unknown Unknown Unknown Unknown No
IBM zFS No No No No No No No No No No Yes No Unknown Unknown Unknown Unknown No
JFS No Unknown Unknown Yes No No No Unknown Unknown Yes Unknown Yes No No Unknown No
Level-D No Unknown Unknown Unknown No Unknown No Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown No
LFS No Unknown Unknown with logfs[178] and others No Unknown No Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown Unknown
LTFS No Unknown Unknown Yes No Yes No No No No No No No No Unknown Unknown No
Lustre No No Partial - under development[179] Yes[180] No Partial - via FUSE Partial - via FUSE No Partial - under development[181] No No No No No Unknown Unknown No
NILFS No Unknown Unknown Yes since kernel 2.6.30 No Unknown No Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown No
NSS Unknown Unknown Unknown with Novell OES2[citation needed] No Unknown No Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown No
NTFS with third-party driver with third-party driver[182] Yes Yes Kernel 2.2 or newer, or with NTFS-3G or ntfsprogs with NTFS-3G or MacFUSE partial read-only in kernel, read-write with NTFS-3G with NTFS-3G read-only with NTFS-3G on Opensolaris Unknown Unknown Partial read-only third-party driver[183] with 3rd-party driver[184] No Unknown Unknown Unknown
NWFS Unknown Unknown Unknown via ncpfs client software[185] No Unknown Yes Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown No
OCFS No Unknown Unknown Yes No Unknown No Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown No
OCFS2 No Unknown Unknown Yes No Unknown No Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown No
ODS-2 No Unknown Unknown Partial read-only with tool or kernel module[186] No Unknown No Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown No
ODS-5 No Unknown Unknown Partial read-only with kernel module[186] No Unknown No Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown No
PramFS No No No Yes No No No No No No No No No No No No No
QFS No Unknown Unknown via client software[187] No Unknown No Unknown Yes Unknown Unknown Unknown No No Unknown Unknown No
ReFS No No Yes since Windows Server 2012 and Windows 8.1 Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown
Reiser4 No Unknown Partial with DiskInternals Linux Reader[169] (read-only) with a kernel patch No No No Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown No
ReiserFS No Unknown Partial with DiskInternals Linux Reader[169] (read-only) Yes since kernel 2.4.1 No No Partial - read only Partial - read only Unknown Unknown Unknown Unknown with 3rd-party app[160] with 3rd-party app[160] Unknown Unknown No
Reliance No No No No No No No No No No No No Yes No Yes Unknown No
Reliance Nitro No No No Yes No No No No No No No No Yes Yes Yes Unknown No
RT-11 No Unknown Unknown Unknown No Unknown No Unknown Unknown Unknown Unknown Unknown No No Yes Unknown No
UDF Unknown Partial read-only support of UDF 1.02 since Win98 and WinME Yes[188] Yes Yes since Mac OS 9 Yes Yes Partial Yes Unknown Unknown Unknown Yes Unknown Unknown Unknown No
UFS1 No Unknown Unknown Partial - read only No Yes Yes Unknown Unknown Unknown Unknown Unknown Unknown Unknown No Unknown Unknown
UFS2 No Unknown Partial - with DiskInternals Linux Reader[169] (read-only) Partial - read only No No Yes Unknown Unknown Unknown Unknown Unknown Unknown Unknown No Unknown Unknown
VMFS2 Unknown Unknown Unknown Unknown No Unknown No Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown No
VMFS3 No Unknown Unknown Partial read-only with vmfs[189] Unknown Unknown No Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown Unknown No
VxFS No Unknown Unknown Yes No Unknown No Unknown Yes Yes Unknown Unknown No No Unknown Yes No
XFS No Unknown Unknown Yes since kernel 2.4 No Unknown Partial: read-only Unknown Unknown Unknown Unknown Unknown No No Unknown Unknown No
ZFS No No No with 3rd Party kernel module[190] or FUSE[191] No with free 3rd-party software[192] Yes No Yes No No No Unknown Unknown Unknown Unknown No
File system DOS Windows 9x Windows NT Linux Mac OS Mac OS X FreeBSD BeOS Solaris AIX z/OS OS/2 Windows CE Windows Mobile VxWorks HP-UX Plan 9

See also[edit]

Notes[edit]

  1. ^ IBM introduced JFS with the initial release of AIX Version 3.1 in 1990. This file system now called JFS1. The new JFS, ported from OS/2 to AIX and Linux, was first shipped in OS/2 Warp Server for e-Business in 1999. It was released as JFS2 on AIX 5L.
  2. ^ through OEM agreement
  3. ^ "Polycenter File System — HELP", Tru64 Unix managers, ORNL 
  4. ^ Microsoft first introduced FAT32 in Windows 95 OSR2 (OEM Service Release 2) and then later in Windows 98. NT-based Windows did not have any support for FAT32 up to Windows NT4; Windows 2000 was the first NT-based Windows OS that received the ability to work with it.
  5. ^ a b Specifications for the Reliance file systems are available here [1].
  6. ^ a b These are the restrictions imposed by the on-disk directory entry structures themselves. Particular Installable File System drivers may place restrictions of their own on file and directory names; and particular and operating systems may also place restrictions of their own, across all filesystems. MS-DOS, Microsoft Windows, and OS/2 disallow the characters \ / : ? * " > < | and NUL in file and directory names across all filesystems. Unix-like systems disallow the characters / and NUL in file and directory names across all filesystems.
  7. ^ a b c d e f For filesystems that have variable allocation unit (block/cluster) sizes, a range of size are given, indicating the maximum volume sizes for the minimum and the maximum possible allocation unit sizes of the filesystem (e.g. 512 bytes and 128 kB for FAT — which is the cluster size range allowed by the on-disk data structures, although some Installable File System drivers and operating systems do not support cluster sizes larger than 32 kB).
  8. ^ While the on-disk filesystem structure uses a 4-byte file length, which allows files up to 4G, the usual disk access APIs use the top three bits of the sector number to specify the drive number, effectively limiting the maximum file size to 512M.
  9. ^ While the on-disk filesystem structure uses a 3-byte sector number, which allows access to 4G of disk space, the usual disk access APIs use the top three bits of the sector number to specify the drive number, effectively limiting the maximum disk size to 512M.
  10. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af In these filesystems the directory entries named "." and ".." have special status. Directory entries with these names are not prohibited, and indeed exist as normal directory entries in the on-disk data structures. However, they are mandatory directory entries, with mandatory values, that are automatically created in each directory when it is created; and directories without them are considered corrupt.
  11. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj The on-disk structures have no inherent limit. Particular Installable File System drivers and operating systems may impose limits of their own, however. MS-DOS/PC DOS do not support full pathnames longer than 66 bytes for FAT12, FAT16 and FAT32 volumes. This limit exists because these operating systems were designed around a fixed-length internal data structure named Current Directory Structure, which holds the absolute paths of the current working directories of all volumes. The FAT12/FAT16 file system implementation under Concurrent DOS and DR DOS 3.31 to 6.0 (prior to 1992 updates) did not impose any such limits on the directory depth due to their internal representation of current working directories as dynamically updated chain of double-linked relative directories. The introduction of a DOS-like CDS (instead of only an emulation thereof) for compatibility purposes with BDOS 7.0 in 1992 imposed the same length limits on PalmDOS, DR DOS 6.0 (since 1992 update), Novell DOS, OpenDOS, etc. as known from MS-DOS/PC DOS. Windows NT does not support full pathnames longer than 32,767 bytes for NTFS. Most Windows programs will fail when full path exceeds 255 characters (including Explorer and CMD.EXE). Linux has a pathname limit of 4,096.
  12. ^ "ProDOS 8 Technical Reference Manual". Retrieved 31 May 2013. 
  13. ^ Beneath Apple ProDOS. Quality Software. 1985. pp. 2–8. ISBN 0-912985-05-4. 
  14. ^ Varies wildly according to block size and fragmentation of block allocation groups.
  15. ^ The CP/M filesystem itself does have limitations in regard to the allowed filename characters to be used, but officially the following characters are not allowed: SPACE < > . , ; : = ? * [ ] % | ( ) / \. CCP reserves the following characters for special purposes: SPACE , = _ . : ;, PIP additionally reserves: < > [ ].
  16. ^ a b "Maximum CP/M-80 2.2 volume size?", comp.os.cpm, Google Groups, retrieved 2009-10-09 
  17. ^ Table "Limits" states a maximum of 255 Unicode characters for the filename [2]
  18. ^ "KB955704". 2009-01-27. "Description of the exFAT file system driver update package [for 32-bit XP]" 
  19. ^ "Interviews/EricSandeen". FedoraProject. 2008-06-09. Retrieved 2009-10-09. 
  20. ^ ext4 1.42 "This release of e2fsprogs has support for file systems > 16 TB"
  21. ^ "msdn TexFAT File Naming Limitations". 2009-10-14. 
  22. ^ a b c d e f g Depends on whether the FAT12, FAT16, and FAT32 implementation has support for long filenames (LFNs). Where it does not, as in OS/2, MS-DOS, Windows 95, Windows 98 in DOS-only mode and the Linux "msdos" driver, file names are limited to 8.3 format of 8-bit characters (space padded in both the basename and extension parts) and may not contain NUL (end-of-directory marker) or character 5 (replacement for character 229 which itself is used as deleted-file marker). Short names also do not normally contain lowercase letters. Also note that a few special names (CON, NUL, LPT1) should be avoided, as some operating systems (notably DOS and windows) effectively reserve them.
  23. ^ Udo Kuhnt, Luchezar Georgiev, Jeremy Davis (2007). FAT+. FATPLUS.TXT, draft revision 2 ([3], [4]).
  24. ^ While FAT32 partitions this large work fine once created, some software won't allow creation of FAT32 partitions larger than 32 GB. This includes, notoriously, the Windows XP installation program and the Disk Management console in Windows 2000, XP, 2003 and Vista. Use FDISK from a Windows ME Emergency Boot Disk to avoid. [5]
  25. ^ a b Depends on kernel version and arch. For 2.4 kernels the max is 2 TB. For 32-bit 2.6 kernels it is 16 TB. For 64-bit 2.6 kernels it is 8 EB.
  26. ^ As Mac OS X is a Unix-like system, which supports : in file names, and which uses / as a pathname component separator, : in file names is represented on disk in HFS and HFS+ as /.
  27. ^ The Mac OS provides two sets of functions to retrieve file names from an HFS Plus volume, one of them returning the full Unicode names, the other shortened names fitting in the older 31 byte limit to accommodate older applications.
  28. ^ HFS Plus mandates support for an escape sequence to allow arbitrary Unicode. Users of older software might see the escape sequences instead of the desired characters.
  29. ^ Docs, Apple 
  30. ^ Docs 
  31. ^ The "." and ".." directory entries in HPFS that are seen by applications programs are a partial fiction created by the Installable File System drivers. The on-disk data structure for a directory does not contain entries by those names, but instead contains a special "start" entry. Whilst on-disk directory entries by those names are not physically prohibited, they cannot be created in normal operation, and a directory containing such entries is corrupt.
  32. ^ This is the limit of the on-disk structures. The HPFS Installable File System driver for OS/2 uses the top 5 bits of the volume sector number for its own use, limiting the volume size that it can handle to 64 GB.
  33. ^ ISO 9660#Restrictions
  34. ^ Through the use of multi-extents, a file can consist of multiple segments, each up to 4 GB in size. See ISO 9660#The 2/4 GB file size limit
  35. ^ Assuming the typical 2048 Byte sector size. The volume size is specified as a 32-bit value identifying the number of sectors on the volume.
  36. ^ Joliet Specification
  37. ^ https://raw.github.com/danrl/lanyfs-docs/master/lanyfs-1.4.txt
  38. ^ "LEAN file system". Freedos-32.sourceforge.net. Retrieved 2013-02-05. 
  39. ^ a b c d e "File, file system, and memory size limits in Minix". Minix1.woodhull.com. Retrieved 2013-02-05. 
  40. ^ a b NSS allows files to have multiple names, in separate namespaces.
  41. ^ a b NTFS allows files to have multiple names, in separate namespaces: Win32, DOS, Win32&DOS, and Posix. Windows APIs create files with Win32 "long" names (1–255 characters), sometimes with an additional "short"/"alias" DOS name in the "8.3" format (12 characters).
  42. ^ a b Richard Russon and Yuval Fledel. "NTFS Documentation". Retrieved 2011-06-26. 
  43. ^ a b "Naming Files, Paths, and Namespaces (MSDN Library article)".  NB: This article includes discussion of the NT & Win32 namespaces used by Windows APIs; these are distinct from the NTFS filename namespaces.
  44. ^ In the Win32 namespace, any UTF-16 code unit (case insensitive) except NUL and \ / : * ? " < > | is allowed; in the Posix namespace, any UTF-16 code unit (case sensitive) except NUL and / is allowed; in the DOS namespace, any character in the U+0021–U+007E range except \ / : * ? " < > | is allowed. Windows APIs require Win32 namespace compatibility, which prevents access to folders & files having only Posix names containing Win32-incompatible characters.
  45. ^ a b This is the limit of the on-disk structures. The NTFS driver for Windows NT limits the volume size that it can handle to 256 TB and the file size to 16 TB respectively."How NTFS Works". 
  46. ^ Some namespaces had lower name length limits. "LONG" had an 80-byte limit, "NWFS" 80 bytes, "NFS" 40 bytes and "DOS" imposed 8.3 filename.
  47. ^ Maximum combined filename/filetype length is 236 bytes; each component has an individual maximum length of 255 bytes.
  48. ^ Maximum pathname length is 4,096 bytes, but quoted limits on individual components add up to 1,664 bytes.
  49. ^ a b QFS allows files to exceed the size of disk when used with its integrated HSM, as only part of the file need reside on disk at any one time.
  50. ^ "MSDN Blogs - Resilient File System, Windows 8 RC's filename length reduced (from 32K to 255) with Windows 8 RTM for NTFS compatibility". Blogs.msdn.com. 2012-01-16. Retrieved 2013-02-05. 
  51. ^ ReiserFS has a theoretical maximum file size of 1 EB, but "page cache limits this to 8TB on architectures with 32 bit int"[6]
  52. ^ "SFS file system". Publib.boulder.ibm.com. Retrieved 2013-02-05. 
  53. ^ This restriction might be lifted in newer versions.
  54. ^ 232 × block size
  55. ^ See manual http://wwwlehre.dhbw-stuttgart.de/~helbig/os/v6/doc/V/dir.html
  56. ^ See manual http://wwwlehre.dhbw-stuttgart.de/~helbig/os/v6/doc/V/fs.html
  57. ^ See "dir (5)" in Volume 1 of the manual http://cm.bell-labs.com/7thEdMan/
  58. ^ The actual maximum was 1,082,201,088 bytes, with 10 direct blocks, 1 singly indirect block, 1 doubly indirect block, and 1 triply indirect block. The 4.0BSD and 4.1BSD versions, and the System V version, used 1,024-byte blocks rather than 512-byte blocks, making the maximum 4,311,812,608 bytes or approximately 4 GB.
  59. ^ a b Maximum file size on a VMFS volume depends on the block size for that VMFS volume. The figures here are obtained by using the maximum block size.
  60. ^ Note that the filename can be much longer XFS#Extended_attributes
  61. ^ a b XFS has a limitation under Linux 2.4 of 64 TB file size, but Linux 2.4 only supports a maximum block size of 2 TB. This limitation is not present under IRIX.
  62. ^ Implemented in later versions as an extension
  63. ^ a b c d e f g h i j k l Some Installable File System drivers and operating systems may not support extended attributes, access control lists or security labels on these filesystems. Linux kernels prior to 2.6.x may either be missing support for these altogether or require a patch.
  64. ^ ext4 has group descriptor, journal and, starting from Linux kernel 3.5, metadata checksumming
  65. ^ a b Concurrent DOS, FlexOS, Multiuser DOS, REAL/32, PalmDOS, Novell DOS, OpenDOS, and DR-DOS can store file owner information in reserved fields of directory entries on FAT12 and FAT16 volumes, if the optional multi-user security module is loaded. If loaded, most external commands invoke support for special /U:owner/group command line options to deal with this extra information.
  66. ^ a b Concurrent DOS, FlexOS, Multiuser DOS, REAL/32, DR DOS, PalmDOS, Novell DOS, OpenDOS, and DR-DOS can store read/write/delete/execute access permissions and file/directory passwords in reserved fields of directory entries on FAT12 and FAT16 volumes. This is an integral part of the design, therefore passwords can be appended to file or directory names with semicolon (for example: dirname;dirpwd\filename;filepwd), the PASSWORD command can be used to control permissions and some commands support a special /P:pwd option to deal with this feature.
  67. ^ a b c d e f File creation and file access timestamps are supported only by DOS 7.0 and higher, and typically only when explicitly enabled.
  68. ^ a b c Some FAT implementations, such as in Linux, show file modification timestamp (mtime) in the metadata change timestamp (ctime) field. This timestamp is however, not updated on file metadata change.
  69. ^ a b Particular Installable File System drivers and operating systems may not support extended attributes on FAT12 and FAT16. The OS/2 and Windows NT filesystem drivers for FAT12 and FAT16 support extended attributes (using a "EA DATA. SF" pseudo-file to reserve the clusters allocated to them). Other filesystem drivers for other operating systems do not.
  70. ^ File permission in 9P are a variation of the traditional Unix permissions with some minor changes, e.g. the suid bit is replaced by a new 'exclusive access' bit.
  71. ^ "As of 10.5 Leopard, Mac OS X has support for Mandatory Labels. See". Trustedbsd.org. Retrieved 2013-02-05. 
  72. ^ The f-node contains a field for a user identifier. This is not used except by OS/2 Warp Server, however.
  73. ^ a b Time the file was recorded on the volume always available; "File Creation Date and Time" available only if the file has an Extended Attribute block.
  74. ^ a b Not applicable to file systems on a read-only medium.
  75. ^ a b Available only if the file has an Extended Attribute block.
  76. ^ Creation time is stored in the backing ext4 filesystem, but is not yet sent to clients.
  77. ^ Lustre has checksums for data over the network, but depends on backing filesystem and hardware for checksums of persistent data
  78. ^ a b c d e Not available with ext3/4, but will be available with ZFS OST/MDT backing filesystems.
  79. ^ NTFS access control lists can express any access policy possible using simple POSIX file permissions (and far more), but use of a POSIX-like interface is not supported without an add-on such as Services for UNIX or Cygwin.
  80. ^ As of Vista, NTFS has support for Mandatory Labels, which are used to enforce Mandatory Integrity Control. See [7]
  81. ^ a b c d e f The local time, timezone/UTC offset, and date are derived from the time settings of the reference/single timesync source in the NDS tree.
  82. ^ a b Novell calls this feature "multiple data streams". Published specifications say that NWFS allows for 16 attributes and 10 data streams, and NSS allows for unlimited quantities of both.
  83. ^ a b Some file and directory metadata is stored on the NetWare server irrespective of whether Directory Services is installed or not, like date/time of creation, file size, purge status, etc; and some file and directory metadata is stored in NDS/eDirectory, like file/object permissions, ownership, etc.
  84. ^ ocfs2 computes and validates checksums of metadata objects like inodes and directories. It also stores an error correction code capable to fixing single-bite errors.
  85. ^ Record Management Services (RMS) attributes include record type and size, among many others.
  86. ^ a b CRCs are employed for certain types of metadata.
  87. ^ a b c d Access-control lists and MAC labels are layered on top of extended attributes.
  88. ^ Some operating systems implemented extended attributes as a layer over UFS1 with a parallel backing file (e.g., FreeBSD 4.x).
  89. ^ MAC/Sensitivity labels are per filesystem. A label per file are not out of the question as a future compatible change but aren't part of any available version of ZFS.
  90. ^ Solaris "extended attributes" are really full-blown alternate data streams, in both the Solaris UFS and ZFS. ZFS also has "system attributes" used for storing MS-DOS/NTFS compatible attributes for use by CIFS; as well as some attributes ported from FreeBSD
  91. ^ McPherson, Amanda (2009-06-22), A Conversation with Chris Mason on BTRfs: the next generation file system for Linux, Linux Foundation, retrieved 2009-09-01 
  92. ^ Wiki, BTRFS, Deduplication 
  93. ^ Linux kernel versions 2.6.12 and newer.
  94. ^ a b c Offline growing/shrinking as well as online growing: "Linux man page for resize2fs(8) (from e2fsprogs 1.41.9)". 
  95. ^ a b c d Off by default.
  96. ^ a b c "6", Parted manual, GNU 
  97. ^ "Write Ahead Physical Block Logging" in NetBSD, provides metadata journaling and consistency as an alternative to softdep.
  98. ^ "OpenBSD growfs(8) manpage". Openbsd.org. 2008-11-28. Retrieved 2013-02-05. 
  99. ^ When used with venti.
  100. ^ Context based symlinks were supported in GFS, GFS2 only supports standard symlinks since the bind mount feature of the Linux VFS has made context based symlinks obsolete
  101. ^ Optional journaling of data
  102. ^ Mac OS System 7 introduced the 'alias', analogous to the POSIX symbolic link but with some notable differences. Not only could they cross file systems but they could point to entirely different file servers, and recorded enough information to allow the remote file system to be mounted on demand. It had its own API that application software had to use to gain their benefits-- this is the opposite approach from POSIX which introduced specific APIs to avoid the symbolic link nature of the link. The Finder displayed their file names in an italic font (at least in Roman scripts), but otherwise they behaved identically to their referent.
  103. ^ "Hard Links on HFS". Developer.apple.com. Retrieved 2013-02-05. 
  104. ^ Metadata-only journaling was introduced in the Mac OS 10.2.2 HFS Plus driver; journaling is enabled by default on Mac OS 10.3 and later.
  105. ^ Although often believed to be case sensitive, HFS Plus normally is not. The typical default installation is case-preserving only. From Mac OS 10.3 on the command newfs_hfs -s will create a case-sensitive new file system. HFS Plus version 5 optionally supports case-sensitivity. However, since case-sensitivity is fundamentally different from case-insensitivity, a new signature was required so existing HFS Plus utilities would not see case-sensitivity as a file system error that needed to be corrected. Since the new signature is 'HX', it is often believed this is a new filesystem instead of a simply an upgraded version of HFS Plus. See Apple's File System Comparisons (which hasn't been updated to discuss HFSX) and Technical Note TN1150: HFS Plus Volume Format (which provides a very technical overview of HFS Plus and HFSX).
  106. ^ Mac OS Tiger (10.4) and late versions of Panther (10.3) provide file change logging (it's a feature of the file system software, not of the volume format, actually). See fslogger.
  107. ^ As of OS X 10.7, HFS+ supports full volume file encryption known as Filevault 2.
  108. ^ Since Mac OS X Snow Leopard, online resizing is supported."How to resize a live partition in Snow Leopard and Lion". 
  109. ^ Particular Installable File System drivers and operating systems may not support case sensitivity for JFS. OS/2 does not, and Linux has a mount option for disabling case sensitivity.
  110. ^ [8][dead link]
  111. ^ a b c d UDF, LFS, and NILFS are log-structured file systems and behave as if the entire file system were a journal.
  112. ^ Can be shrunk online by migrating files off an OST and removing the OST, or offline with ext3/4 backing filesystems by shrinking the OST filesystem
  113. ^ a b c d Case-sensitivity/Preservation depends on client. Windows, DOS, and OS/2 clients don't see/keep case differences, whereas clients accessing via NFS or AFP may.
  114. ^ a b The file change logs, last entry change timestamps, and other filesystem metadata, are all part of the extensive suite of auditing capabilities built into NDS/eDirectory called NSure Audit. (Filesystem Events tracked by NSure)
  115. ^ As of Windows Vista, NTFS fully supports soft links. See this Microsoft article on Vista kernel improvements. NTFS 5.0 (Windows 2000) and higher can create junctions, which allow any valid local directory (but not individual files) ("target" of junction) to be mapped to an NTFS version thereof ("source" = location of junction). The source directory must lie on an NTFS 5+ partition, but the target directory can lie on any valid local partition and needn't be NTFS. Junctions are implemented through reparse points, which allow the normal process of filename resolution to be extended in a flexible manner.
  116. ^ a b NTFS stores everything, even the file data, as meta-data, so its log is closer to block journaling.
  117. ^ While NTFS itself supports case sensitivity, the Win32 environment subsystem cannot create files whose names differ only by case for compatibility reasons. When a file is opened for writing, if there is any existing file whose name is a case-insensitive match for the new file, the existing file is truncated and opened for writing instead of a new file with a different name being created. Other subsystems like e. g. Services for Unix, that operate directly above the kernel and not on top of Win32 can have case-sensitivity.
  118. ^ NTFS does not internally support snapshots, but in conjunction with the Volume Shadow Copy Service can maintain persistent block differential volume snapshots.
  119. ^ Rick Vanover. "Windows Server 8 data deduplication". Retrieved 2011-12-02. 
  120. ^ "How to Shrink and Extend NTFS Volumes in Windows". Bleepingcomputer.com. Retrieved 2013-02-05. 
  121. ^ a b Available only in the "NFS" namespace.
  122. ^ Limited capability. Volumes can span physical disks (volume segment)
  123. ^ OCFS2 supports creating multiple write-able snapshots of regular files using REFLINK.
  124. ^ a b These are referred to as "aliases".
  125. ^ Symlinks only visible to NFS clients. References and Off-Disk Pointers (ODPs) provide local equivalent.
  126. ^ Full block journaling for ReiserFS was not added to Linux 2.6.8 for obvious reasons.[why?]
  127. ^ a b Reiser4 supports transparent compression and encryption with the cryptcompress plugin which is the default file handler in version 4.1.
  128. ^ a b File system implements reliability via atomic transactions.
  129. ^ "Soft dependencies" (softdep) in NetBSD, called "soft updates" in FreeBSD provide meta-data consistency at all times without double writes (journaling).
  130. ^ Block level journals can be added by using gjournal module in FreeBSD.
  131. ^ http://docs.oracle.com/cd/E19253-01/817-5093/fsoverview-43/index.html
  132. ^ "FreeBSD growfs(8) manpage". Freebsd.org. 2012-04-30. Retrieved 2013-02-05. 
  133. ^ System V Release 4, and some other Unix systems, retrofitted symbolic links to their versions of the Version 7 Unix file system, although the original version didn't support them.
  134. ^ VxFS provides an optional feature called "Storage Checkpoints" which allows for advanced file system snapshots.
  135. ^ Optionally no on IRIX.
  136. ^ a b ZFS is a transactional filesystem using copy-on-write semantics, guaranteeing an always-consistent on-disk state without the use of a traditional journal. However, it does also implement an intent log to provide better performance when synchronous writes are requested.
  137. ^ "How to resize ZFS". 
  138. ^ a b Variable block size refers to systems which support different block sizes on a per-file basis. (This is similar to extents but a slightly different implementational choice.) The current implementation in UFS2 is read-only.
  139. ^ Btrfs can only inline files smaller than 3916B with its metadata"Mailing list discussion". 
  140. ^ only for .REL (record structured) files, up to 254 bytes/record
  141. ^ a b c d Fragments were planned, but never actually implemented on ext2 and ext3.
  142. ^ e2compr, a set of patches providing block-based compression for ext2, has been available since 1997, but has never been merged into the mainline Linux kernel.
  143. ^ a b SuperStor in DR DOS 6.0 and PC DOS 6.1, DoubleSpace in MS-DOS 6.0, DriveSpace in MS-DOS 6.22, Windows 95 and Windows 98, and Stacker in Novell DOS 7, OpenDOS 7.01, DR-DOS 7.02/7.03 and PC DOS 7.0/2000 were data compression schemes for FAT.
  144. ^ a b c d Other block:fragment size ratios supported; 8:1 is typical and recommended by most implementations.
  145. ^ Only for "stuffed" inodes
  146. ^ "AIX documentation: JFS data compression". IBM. 
  147. ^ Only if formatted with 4kB-sized clusters or smaller
  148. ^ Each possible size (in sectors) of file tail has a corresponding suballocation block chain in which all the tails of that size are stored. The overhead of managing suballocation block chains is usually less than the amount of block overhead saved by being able to increase the block size but the process is less efficient if there is not much free disk space.
  149. ^ In "extents" mode.
  150. ^ Depends on UDF implementation.
  151. ^ When enabled, ZFS's logical-block based compression behaves much like tail-packing for the last block of a file.
  152. ^ a b c AncientFS
  153. ^ a b c Ext2Fsd is an open source ext2/ext3/ext4 kernel-level file system driver for Windows systems (NT/2K/XP/VISTA/7, X86/AMD64) that provides both read/write access to the file system. Currently, does not fully support extents (no size truncating/extending, no file deletion), a default feature of ext4. [9]
  154. ^ a b Ext2 IFS for Windows provides kernel-level read/write access to ext2 and ext3 volumes in Windows NT4, 2000, XP, Vista and Windows 2008. Does not support inodes size above 128 bytes and does not support ext4.[10]
  155. ^ a b c Ext2Read is an explorer-like utility to explore ext2/ext3/ext4 file systems that provides read-only access to the file system. It supports extents, large inodes, and LVM2 volumes.Ext2Read
  156. ^ a b c Fuse-ext2 is a multi OS FUSE module to mount ext2 and ext3 file system devices and/or images with read and write support.[11]
  157. ^ a b c Paragon ExtFS for Mac is a low-level file system driver specially developed to bridge file system incompatibility between Linux and Mac by providing full read/write access to the Ext2, Ext3 and Ext4 file systems under Mac OS X.[12]
  158. ^ Ext2fsx is the first and old implementation of the Ext2 (Linux) filesystem for Mac OS X.[13]
  159. ^ OS/2 ext2 Driver
  160. ^ a b c d e f See Total Commander, which supports accessing ext2, ext3, and ReiserFS from Windows, Windows CE, and Windows Mobile.
  161. ^ a b ext4fuse is a free software multi OS FUSE module to mount ext4 file system devices and/or images with read-only support. [14]
  162. ^ a b c Files, Databases, and Persistent Storage. MSDN.
  163. ^ a b c Via dosFs.
  164. ^ Native FAT32 support with MS-DOS 7.10 and 8.0. Loadable FAT32 support for any DOS since 3.31 with DRFAT32 redirector driver. Native FAT32 support since OEM DR-DOS 7.04, bootable FAT32 support since OEM DR-DOS 7.06. Native FAT32 support with OEM PC DOS 7.10.
  165. ^ "OS/2 and eComstation FAT32 Driver". Hobbes.nmsu.edu. Retrieved 2013-02-05. 
  166. ^ "How to mount FFS partition under Linux - NetBSD Wiki". Wiki.netbsd.se. Archived from the original on March 19, 2008. Retrieved 2009-10-09. 
  167. ^ a b c d Via Plan 9 from User Space; initial checkin "fossil: import from plan 9". Retrieved 2013-11-24. 
  168. ^ a b c d Cross-platform Drive Solutions. "Sharing Disks - Windows Products". Macwindows.com. Retrieved 2013-02-05. 
  169. ^ a b c d e DiskInternals Linux Reader is an application for Windows NT that allows reading of Ext2/3/4, ReiserFS, Reiser4, HFS/HFS+, FAT/exFAT, NTFS, ReFS, and UFS2 filesystems.
  170. ^ Gagne, Ken (2009-08-31). "Losing legacy data to Snow Leopard". Computerworld. Retrieved 2009-09-07. 
  171. ^ "hfsutils at FreshPorts". Freshports.org. Retrieved 2013-02-05. 
  172. ^ "hfs at FreshPorts". Freshports.org. Retrieved 2013-02-05. 
  173. ^ "OS/2 HFS Driver". Hobbes.nmsu.edu. Retrieved 2013-02-05. 
  174. ^ "Catacombae HFSExplorer". Hem.bredband.net. Retrieved 2013-02-05. 
  175. ^ "DOS/Win 9x HPFS Driver". Hobbes.nmsu.edu. Retrieved 2013-02-05. 
  176. ^ Win NT 4.0 HPFS Driver
  177. ^ [15]
  178. ^ logfs
  179. ^ http://wiki.lustre.org/index.php/Windows_Native_Client
  180. ^ http://wiki.lustre.org/index.php?title=Main_Page
  181. ^ http://wiki.lustre.org/index.php/FAQ_-_OS_Support
  182. ^ "NTFS for Windows 98". Download.chip.eu. Retrieved 2013-02-05. 
  183. ^ "OS/2 NTFS Driver". Hobbes.nmsu.edu. Retrieved 2013-02-05. 
  184. ^ Tuxera NTFS for Windows CE. See "article". Archived from the original on 18 Sep 2012.  and announcement.
  185. ^ ncpfs
  186. ^ a b VMS2Linux
  187. ^ Using SAM-QFS on Linux Clients
  188. ^ "Understanding the difference between the Live File System and Mastered disc formats". Which CD or DVD format should I use?. Microsoft. Retrieved 2008-11-22. 
  189. ^ vmfs
  190. ^ Native ZFS for Linux
  191. ^ ZFS on FUSE
  192. ^ Mac ZFS

External links[edit]