1 .. SPDX-License-Identifier: GPL-2.0
2
3 Blocks
4 ------
5
6 ext4 allocates storage space in units of “bl
7 sectors between 1KiB and 64KiB, and the number
8 integral power of 2. Blocks are in turn groupe
9 block groups. Block size is specified at mkfs
10 4KiB. You may experience mounting problems if
11 page size (i.e. 64KiB blocks on a i386 which o
12 pages). By default a filesystem can contain 2^
13 feature is enabled, then a filesystem can have
14 of structures is stored in terms of the block
15 in and not the absolute offset on disk.
16
17 For 32-bit filesystems, limits are as follows:
18
19 .. list-table::
20 :widths: 1 1 1 1 1
21 :header-rows: 1
22
23 * - Item
24 - 1KiB
25 - 2KiB
26 - 4KiB
27 - 64KiB
28 * - Blocks
29 - 2^32
30 - 2^32
31 - 2^32
32 - 2^32
33 * - Inodes
34 - 2^32
35 - 2^32
36 - 2^32
37 - 2^32
38 * - File System Size
39 - 4TiB
40 - 8TiB
41 - 16TiB
42 - 256TiB
43 * - Blocks Per Block Group
44 - 8,192
45 - 16,384
46 - 32,768
47 - 524,288
48 * - Inodes Per Block Group
49 - 8,192
50 - 16,384
51 - 32,768
52 - 524,288
53 * - Block Group Size
54 - 8MiB
55 - 32MiB
56 - 128MiB
57 - 32GiB
58 * - Blocks Per File, Extents
59 - 2^32
60 - 2^32
61 - 2^32
62 - 2^32
63 * - Blocks Per File, Block Maps
64 - 16,843,020
65 - 134,480,396
66 - 1,074,791,436
67 - 4,398,314,962,956 (really 2^32 due to f
68 * - File Size, Extents
69 - 4TiB
70 - 8TiB
71 - 16TiB
72 - 256TiB
73 * - File Size, Block Maps
74 - 16GiB
75 - 256GiB
76 - 4TiB
77 - 256TiB
78
79 For 64-bit filesystems, limits are as follows:
80
81 .. list-table::
82 :widths: 1 1 1 1 1
83 :header-rows: 1
84
85 * - Item
86 - 1KiB
87 - 2KiB
88 - 4KiB
89 - 64KiB
90 * - Blocks
91 - 2^64
92 - 2^64
93 - 2^64
94 - 2^64
95 * - Inodes
96 - 2^32
97 - 2^32
98 - 2^32
99 - 2^32
100 * - File System Size
101 - 16ZiB
102 - 32ZiB
103 - 64ZiB
104 - 1YiB
105 * - Blocks Per Block Group
106 - 8,192
107 - 16,384
108 - 32,768
109 - 524,288
110 * - Inodes Per Block Group
111 - 8,192
112 - 16,384
113 - 32,768
114 - 524,288
115 * - Block Group Size
116 - 8MiB
117 - 32MiB
118 - 128MiB
119 - 32GiB
120 * - Blocks Per File, Extents
121 - 2^32
122 - 2^32
123 - 2^32
124 - 2^32
125 * - Blocks Per File, Block Maps
126 - 16,843,020
127 - 134,480,396
128 - 1,074,791,436
129 - 4,398,314,962,956 (really 2^32 due to f
130 * - File Size, Extents
131 - 4TiB
132 - 8TiB
133 - 16TiB
134 - 256TiB
135 * - File Size, Block Maps
136 - 16GiB
137 - 256GiB
138 - 4TiB
139 - 256TiB
140
141 Note: Files not using extents (i.e. files usin
142 placed within the first 2^32 blocks of a files
143 must be placed within the first 2^48 blocks of
144 clear what happens with larger filesystems.
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