What sizes should you allocate to the /, /boot, /home and swap

/boot does not need a lot of space (say 1 Go).

/swap used to be twice the RAM on old configurations, now with more than 2 Go of ram, you won't need more than 2 Go of swap.

/ is important and difficult to scale : will you install a lot of stuff ? Will you use other directories than /home to save things (web server/ftp files for example) ? If you don't, 10 Go would be very good for a ubuntu.

/home need to be as big as possible for you to enjoy your linux distro

Create swap at the beginning of your drive, 2x your physical RAM is a good guideline. Boot can be pretty small if you want to make it a separate partition, a gig or less. You want make your root partition big enough that you have space to install more applications later but not so big that you feel cramped in your home partition.

Here's what I would do if I was building your system:

• 4GB swap
• <1GB boot
• 30GB /
• the rest /home

I'm sure that there are many interesting reasons for having separate partitions, but I've found it easiest (and more flexible) to just create / and nothing else. A swap partition might be OK if your machine is low on RAM (2GB is on the edge) and/or you anticipate heavily using the machine. I've found that 1.5x RAM size is a good swap size.

A clean installation of Ubuntu 9.10 requires an odd 2.5 GB on disk. Is up to you to decide how much space you need for extra programs and data.

IMHO you don't need to have /boot and /home as separate partitions.

Unless you exactly know what you're doing and have some real reason to do that, splitting your filesystems into multiple places does not make much more sense than a all-in-one-place approach for the typical home use.

You can easily install GRUB on the MBR to have a dual-boot machine and you can create a single partition (mounted as /) for both system files and users home directories.

Speaking of the /swap partition:2GB of installed RAM make very unlikely that you ever need a swap space, except when you will put your PC in suspend / sleep mode. In this scenario the RAM image (part of it?) will be dumped on disk, so you can live happy with a swap partition = RAM size.