Reiser4 is the successor filesystem for ReiserFS, developed from scratch by Namesys and Hans Reiser. It is very efficient for handling small files (often used in
/var for this purpose) and includes features such as cheap transparent compression and block suballocation. Because it is an atomic file system "your file system operations either entirely occur, or they entirely don't, and they do not corrupt due to half occurring." Benchmarks with other linux filesystems are also available.
- Reiser4 requires a patched kernel
- It consumes a little more CPU than other filesystems
- Even LILO as the only bootloader officially supporting Reiser4 seems to have issues with it when
/bootis formatted as Reiser4
- It is still not considered stable
1. Install the AUR package
2. You will need a reiser4 patched kernel. Patches can be found here http://sourceforge.net/projects/reiser4/files/reiser4-for-linux-3.x/
3. Bootloader (Optional, only needed if you want to format your
/ (root) as reiser4)
a) Recommended: make a small (as mentioned above, 20-200mb) partition for
/boot with a filesystem other than Reiser4 with GParted, and then copy your
/boot folder to the partition. Update your bootloader config accordingly, eg. with Grub2 do:
# grub-mkconfig -o /boot/grub/grub.cfg
b) If you wish to put everything including
/boot on a Reiser4 partition you will need to use LILO. This is not advised, as you will probably get an error when trying to update
Moving to Reiser4
In the next steps we will copy the data from your current root partition to the new Reiser4 partitions. Make sure you have enough disk space on the Reiser4 partition with:
# df -h
# fdisk -l * /dev/sda1: (10 Gb, 5 Gb free); Reiserfs /mnt/reiser4 * /dev/sda2: (10 Gb, 10 Gb free); Reiser4 / * /dev/sda3: (200 Mb, 180 Mb free); ext2 /boot
Run the following commands:
mkfs.reiser4 /dev/sdaX mkdir /mnt/reiser4 mount -t reiser4 /dev/sdaX /mnt/reiser4
It is recommended that you use the Cryptcompress plugin by formatting with the following command:
mkfs.reiser4 -o create=ccreg40,compress=lzo1 /dev/sdaX
Once the partition is formatted, copy you current system to the new partition and create the system directories. You may either do this from Arch Linux, or to make it easier (so that you do not have to use makedev later), just boot up with the Gparted LiveCD and mount both your new Reiser4 partition and your current root partition. Then, just copy everything over (as root) like so:
cd /mnt mkdir oldroot mkdir reiser4 mount /dev/sdaX oldroot mount /dev/sdaY reiser4 (the Reiser4 partition) cp -R -a /mnt/oldroot/* /mnt/reiser4/
Then, you need to mount your
/boot partition, and if you have not already, copy
/boot from your original root partition over to it.
mkdir bootpart mount /dev/sdaZ bootpart cp -R -a /mnt/oldroot/boot/* /mnt/bootpart/
Do not forget to edit your bootloader's config appropriately (see examples at the bottom of the article).
Note: If you can confirm that Reiser4 works for you, you should format the old root partition.
# # /etc/fstab: static file system information # # <file system> <dir> <type> <options> <dump> <pass> /dev/sda1 / reiser4 defaults,noatime,notail 0 1 /dev/sda2 /mnt/oldroot ext4 defaults 0 0 /dev/sda3 /boot ext2 defaults 0 1
# (0) Arch Linux title Arch Linux set root=(hd0,msdos3) kernel /vmlinuz-linux root=/dev/sda3 ro noatime notail acl init=/usr/bin/bootchartd initrd /initramfs-linux.img # (1) Arch Linux title Arch Linux Fallback set root=(hd0,msdos3) kernel /vlinuz-linux root=/dev/sda3 ro initrd /initramfs-linux-fallback.img
grub-mkconfig to update your config:
# grub-mkconfig -o /boot/grub/grub.cfg
# # /etc/lilo.conf # boot=/dev/hda # This line often fixes L40 errors on bootup # disk=/dev/hda bios=0x80 default=Arch4 timeout=20 lba32 prompt compact image=/boot/vmlinuz-linux label=Arch4 root=/dev/hda5 append="video=vesafb:1024x768-24@56,ywrap,mtrr splash=verbose,theme:darch console=tty1 resume2=swap:/dev/hdb1" initrd=/boot/initramfs-linux.img read-only image=/boot/vmlinuz-linux label=Arch root=/dev/hda3 append="video=vesafb:1024x768-24@56,ywrap,mtrr splash=verbose,theme:darch console=tty1 resume2=swap:/dev/hdb1" initrd=/boot/initramfs-linux.img read-only
Run lilo to update your config:
- Permissions: chown -R username.group <userdir>
- If you have problem with su command after the change of fs, you should reinstall coreutils package.