从 ext3 文件系统复制的文件不适合相同大小的 ext4 文件系统。
如何重现：
创建两个 1GB 文件，
为每个设置循环设备，
创建文件系统1个ext3，1个ext4，
山，
rsync 文件从 /usr/lib 到 ext3 文件夹直到满，
尝试将文件从 ext3 文件夹同步到 ext4，但由于磁盘空间问题而失败。
我希望 ext3 文件夹中的所有文件都适合 ext4 文件夹
（查看日志，下一个要复制的文件大于可用空间，并且还有一些文件需要复制）
有人可以解释为什么吗？或者更好的是如何使用 ext4 获得相同或更多的可用磁盘空间？
这是debian8系统
root@blackoil:~# uname -a
Linux blackoil 3.16.0-4-amd64 #1 SMP Debian 3.16.7-ckt7-1 (2015-03-01) x86_64 GNU/Linux
root@blackoil:~# dd if=/dev/zero of=e3fs bs=1M count=1000
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 6.07722 s, 173 MB/s
root@blackoil:~# dd if=/dev/zero of=e4fs bs=1M count=1000
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 6.21495 s, 169 MB/s
root@blackoil:~# losetup /dev/loop3 e3fs
root@blackoil:~# losetup /dev/loop4 e4fs
root@blackoil:~# mkfs.ext3 -m 0 /dev/loop3
mke2fs 1.42.12 (29-Aug-2014)
Discarding device blocks: done
Creating filesystem with 256000 4k blocks and 64000 inodes
Filesystem UUID: 8871cd27-5c82-4fa9-acaa-11c2ca200d08
Superblock backups stored on blocks:
32768, 98304, 163840, 229376
Allocating group tables: done
Writing inode tables: done
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done
root@blackoil:~# mkfs.ext4 /dev/loop4
mke2fs 1.42.12 (29-Aug-2014)
Discarding device blocks: done
Creating filesystem with 256000 4k blocks and 64000 inodes
Filesystem UUID: 71b69de9-0858-4189-8e1f-907efd61f51d
Superblock backups stored on blocks:
32768, 98304, 163840, 229376
Allocating group tables: done
Writing inode tables: done
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done
root@blackoil:~# mkdir -p /mnt/e3
root@blackoil:~# mkdir -p /mnt/e4
root@blackoil:~# dumpe2fs /dev/loop3
dumpe2fs 1.42.12 (29-Aug-2014)
Filesystem volume name: <none>
Last mounted on: <not available>
Filesystem UUID: 8871cd27-5c82-4fa9-acaa-11c2ca200d08
Filesystem magic number: 0xEF53
Filesystem revision #: 1 (dynamic)
Filesystem features: has_journal ext_attr resize_inode dir_index filetype sparse_super large_file
Filesystem flags: signed_directory_hash
Default mount options: user_xattr acl
Filesystem state: clean
Errors behavior: Continue
Filesystem OS type: Linux
Inode count: 64000
Block count: 256000
Reserved block count: 0
Free blocks: 247557
Free inodes: 63989
First block: 0
Block size: 4096
Fragment size: 4096
Reserved GDT blocks: 62
Blocks per group: 32768
Fragments per group: 32768
Inodes per group: 8000
Inode blocks per group: 500
Filesystem created: Mon Jul 20 15:21:53 2015
Last mount time: n/a
Last write time: Mon Jul 20 15:21:53 2015
Mount count: 0
Maximum mount count: -1
Last checked: Mon Jul 20 15:21:53 2015
Check interval: 0 (<none>)
Reserved blocks uid: 0 (user root)
Reserved blocks gid: 0 (group root)
First inode: 11
Inode size: 256
Required extra isize: 28
Desired extra isize: 28
Journal inode: 8
Default directory hash: half_md4
Directory Hash Seed: a35b09fe-b755-49b6-a94d-eb8f2960e5a6
Journal backup: inode blocks
Journal features: (none)
Journal size: 16M
Journal length: 4096
Journal sequence: 0x00000001
Journal start: 0
root@blackoil:~# dumpe2fs /dev/loop4
dumpe2fs 1.42.12 (29-Aug-2014)
Filesystem volume name: <none>
Last mounted on: <not available>
Filesystem UUID: 71b69de9-0858-4189-8e1f-907efd61f51d
Filesystem magic number: 0xEF53
Filesystem revision #: 1 (dynamic)
Filesystem features: has_journal ext_attr resize_inode dir_index filetype extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize
Filesystem flags: signed_directory_hash
Default mount options: user_xattr acl
Filesystem state: clean
Errors behavior: Continue
Filesystem OS type: Linux
Inode count: 64000
Block count: 256000
Reserved block count: 12800
Free blocks: 247562
Free inodes: 63989
First block: 0
Block size: 4096
Fragment size: 4096
Reserved GDT blocks: 62
Blocks per group: 32768
Fragments per group: 32768
Inodes per group: 8000
Inode blocks per group: 500
Flex block group size: 16
Filesystem created: Mon Jul 20 15:22:16 2015
Last mount time: n/a
Last write time: Mon Jul 20 15:22:16 2015
Mount count: 0
Maximum mount count: -1
Last checked: Mon Jul 20 15:22:16 2015
Check interval: 0 (<none>)
Lifetime writes: 16 MB
Reserved blocks uid: 0 (user root)
Reserved blocks gid: 0 (group root)
First inode: 11
Inode size: 256
Required extra isize: 28
Desired extra isize: 28
Journal inode: 8
Default directory hash: half_md4
Directory Hash Seed: 33846c93-9d1a-4117-a7c8-1566e96e8e73
Journal backup: inode blocks
Journal features: (none)
Journal size: 16M
Journal length: 4096
Journal sequence: 0x00000001
Journal start: 0
root@blackoil:~# mount /dev/loop3 /mnt/e3
root@blackoil:~# mount /dev/loop4 /mnt/e4
root@blackoil:~# rsync -a /usr/lib /mnt/e3
rsync: recv_generator: mkdir "/mnt/e3/lib/python2.6/xml/sax" failed: No space left on device (28)
*** Skipping any contents from this failed directory ***
rsync: write failed on "/mnt/e3/lib/python2.6/httplib.py": No space left on device (28)
rsync error: error in file IO (code 11) at receiver.c(393) [receiver=3.1.1]
root@blackoil:~# df |grep '/mnt/e'
/dev/loop3 991512 991512 0 100% /mnt/e3
/dev/loop4 991512 1264 922664 1% /mnt/e4
root@blackoil:~# cd /mnt/e3
root@blackoil:/mnt/e3# rsync -a . /mnt/e4
rsync: write failed on "/mnt/e4/lib/pepperflashplugin-nonfree/libpepflashplayer.so": No space left on device (28)
rsync error: error in file IO (code 11) at receiver.c(393) [receiver=3.1.1]
root@blackoil:/mnt/e3# df | grep '/mnt/e'
/dev/loop3 991512 991512 0 100% /mnt/e3
/dev/loop4 991512 959372 0 100% /mnt/e4
root@blackoil:/mnt/e3# df -i | grep '/mnt/e'
/dev/loop3 64000 8939 55061 14% /mnt/e3
/dev/loop4 64000 8531 55469 14% /mnt/e4
root@blackoil:/mnt/e3# rsync -av . /mnt/e4
sending incremental file list
lib/pepperflashplugin-nonfree/
lib/pepperflashplugin-nonfree/libpepflashplayer.so
lib/pepperflashplugin-nonfree/manifest.json
lib/pepperflashplugin-nonfree/pubkey-google.txt
lib/pkgconfig/dbus-python.pc
lib/pkgconfig/geoclue-2.0.pc
lib/pkgconfig/gnome-system-tools.pc
lib/pkgconfig/keybinder.pc
lib/pkgconfig/libgdiplus.pc
lib/pkgconfig/libquvi-scripts.pc
lib/pkgconfig/libwnck-1.0.pc
lib/pkgconfig/libxfce4menu-0.1.pc
lib/pkgconfig/libxklavier.pc
lib/pkgconfig/notify-python.pc
lib/pkgconfig/pm-utils.pc
lib/pkgconfig/tomboy-addins.pc
lib/pkgconfig/unique-1.0.pc
lib/pkgconfig/xkbcomp.pc
lib/pkgconfig/xorg-wacom.pc
lib/pm-utils/
( ...... some removed due to 30000 lines limit posting question)
rsync: write failed on "/mnt/e4/lib/pepperflashplugin-nonfree/libpepflashplayer.so": No space left on device (28)
rsync error: error in file IO (code 11) at receiver.c(393) [receiver=3.1.1]
root@blackoil:/mnt/e3# df |grep 'mnt/e'
/dev/loop3 991512 991512 0 100% /mnt/e3
/dev/loop4 991512 959372 0 100% /mnt/e4
root@blackoil:/mnt/e3# ls -l /mnt/e4/lib/pepperflashplugin-nonfree/libpepflashplayer.so
ls: cannot access /mnt/e4/lib/pepperflashplugin-nonfree
/libpepflashplayer.so: No such file or directory
root@blackoil:/mnt/e3# ls -l lib/pepperflashplugin-nonfree/libpepflashplayer.so
-rw-r--r-- 1 root root 17370752 Mar 14 09:08 lib/pepperflashplugin-nonfree/libpepflashplayer.so
root@blackoil:/mnt/e3# mount |grep 'mnt/e'
/dev/loop3 on /mnt/e3 type ext3 (rw,relatime,data=ordered)
/dev/loop4 on /mnt/e4 type ext4 (rw,relatime,data=ordered)
答案1
它在您的储备块计数中：
ext3：块计数：256000 保留块计数：0
ext4：块数：256000 保留块数：12800
修复：#tune2fs -m 0 e4fs