Reiser4

Reiser4 is the latest version of the Reiser File System. This guide will explain how to install Gentoo using the Reiser4 filesystem.

What is Reiser4?
Reiser4 is a filesystem type that was under development by Namesys. It is presently being maintained by former Namesys developers.

Why should I use Reiser4?
The advantages of Reiser4 become evident for high-load systems with thousands of files to serve. Because of its extensibility with plugins, and its minimalistic approach it is very interesting for system developers.

File System Stability
Reiser4 is not a finished product. It should not be used for production machines; mission critical machines should use a file system that has been established.

Preparation
You will need a LiveCD/DVD/USB that supports formatting the storage medium with Reiser4. SystemRescueCD is one such LiveCD that you can use to prepare your storage medium(s), but you may use any one you wish, as long as it supports Reiser4 and has reiser4progs package.

Installation
Follow the Gentoo Handbook for your platform, but instead of the Gentoo LiveCD or Gentoo Minimal Install CD, use the LiveCD/DVD/USB discussed earlier. You will still be able to build a Gentoo system even without the Gentoo installation medium.

When you come to the portion regarding emerging file system utilities, here's what you'll need:

Use mkfs.reiser4 to create the Reiser4 filesystem on your selected partitions. You can also tweak its settings by using the -o flag. Refer to its man page, should you need any help. Below is an example — creating a filesystem with enabled compression and filename hashing function set to tea_hash

You can view the default settings and possible options by typing the following command:

Patching the kernel
Get the reiser4 patch and apply to your kernel sources. Then run make menuconfig and enable Reiser4 under the File systems menu.

After finishing the config, build and install the kernel as usual. Refer to the Gentoo installation handbook for more information.