How much disk space should I devote to my Linux / partition?
Solution 1:
I think 10 GB is plenty.
I am running a Ubuntu server within 10GB (including /home) and it is puffing along fine. Excluding my files, the system takes up less than 4GB. If you ever find yourself pressed for space, you can always resize the partitions at a later date.
Solution 2:
Use LVM and a filesystem that supports online resizing (includes ext3/4 with the right mkfs options, which should be the default) and then you can easily grow it if needed.
I'd start with 2–4G on a server, maybe 5G on a desktop, because growing it is trivial with LVM.
Or, alternatively, there really isn't anything wrong with everything on / for a desktop.
Solution 3:
It highly depends upon the Linux distribution you are going to install,
Because DSL(Damn Small Linux) or Puppy Linux are mere 60 -70 'MB' whereas Fedora goes in 4-5 GB and Ubuntu in 2-3 GB
It even depends upon how much you are going to use Linux, i.e the softwares you are going to install
For Latest Fedora releases 10 GB is enough.
For ubuntu use 5 GB
Solution 4:
Depends on how are you going to use /tmp, as it resides in /. Building a DVD may take a lot of space there
Solution 5:
Keep in mind that the biggest folders in your file system are (on a debian system, but its a good guideline):
/usr: all user programs (/usr/bin), libraries (/usr/lib), documentation (/usr/share/doc), etc., are in this directory. This part of the file system needs most of the space. You should provide at least 500 MB of disk space. If you want to install more packages you should increase the amount of space you give this directory.
/home: every user will put his data into a subdirectory of this directory. The size of this depends on how many users will be using the system and what files are to be stored in their directories. Depending on your planned usage you should reserve about 100 MB for each user, but adapt this value to your needs.
/var: all variable data like news articles, e-mails, web sites, APT's cache, etc. will be placed under this directory. The size of this directory depends greatly on the usage of your computer, but for most people will be dictated by the package management tool's overhead. If you are going to do a full installation of just about everything Debian has to offer, all in one session, setting aside 2 or 3 gigabytes of space for /var should be sufficient. If you are going to install in pieces (that is to say, install services and utilities, followed by text stuff, then X, ...), you can get away with 300 - 500 megabytes of in /var. If hard drive space is at a premium and you don't plan on using APT, at least not for major updates, you can get by with as little as 30 or 40 megabytes in /var.
As you will have a different /home partition, you could go with as little as 4GB (plus /home, /var (50MB), /boot (100MB) and swap (300MB-2GB)), with a fully working system.