hd partition sizes, particularly on smallish drives
 

i'm setting a couple friends up with linux, and they both have computers with small hard drives: one is 6 GB and the other (i believe) is 4 or 4.5 GB. what should i be thinking about when i plan the partitions?

my forays into the world of google have shown me a lot of answers, but generally for larger drives. two general systems seem pretty common: /, /home, swap, and possibly /usr get their own partitions; or /boot, /, /home, /opt, /tmp, /usr, /var and swap all get their own partitions.

should i consider lvm?

how should i make these sorts of decisions... particularly, i would like to know how to extend this process next time i have to partition drives (such as when i finally getting around to copying my old files from my old 15gb windows drive).

in case the following information might be helpful, my friends (for whom i'm setting up the computers) and i are all students, so will be using the computers primarily for open/star office, internet browsing, and playing cd's. i'll be installing debian sarge (testing), kde, and probably the latest and greatest of the 2.4 kernel.

If you have a small hard drive, then you might want to use a basic setup with a small boot partition, a swap partition and a root partition. That way, you will not have say the /usr partition fill up on you, while the /home has plenty of room.

On a drive that small, there's not much need to plan partitions at all. Unless you plan to be reformatting a lot, you might as well just use the traditional / and /swap (you have to have these two), and all the folders that (as you mention) can be separate partitons if desired, will simply be folders in the / directory. Many distribution installers will make /boot as a separate partition, but this is not strictly necessary, and need only be 30-50 MB in size in any case. /swap is traditionally 2X RAM up to 512MB in size (although RedHat variants will give you an error in the installer if you don't actually set your swap partition to literally 2X RAM, even if you have a GB of RAM)-- more than 512MB for swap is generally considered wasted space.

Putting /home on a separate partition is mildly useful under certain circumstances (the aforementioned reformat and reinstall, or multiple distros install, or a lot of distro-swapping), but again, you don't have enough space on those drives for more than one distro, if the distro breaks so badly that you have to reformat and reinstall this is most likely going to happen before you have anything in the /home folder that needs saving, except a couple of settings (and those can be easily recreated), and if and when you get more space for personal files, these can be saved on a new drive/partition mounted into the /home folder, rather than in the /home folder itself, so I don't so much see the big whoop about a separate /home partition.

/usr is where most programs are installed; alternatively, some programs (notably KDE) may install themselves in /opt. /var is for log files; this normally won't get very big unless you're running a mail or web server. /tmp is (not surprisingly) where temporary files are stored.... temporarily, mostly. The main issue is the extraction of large install files, especially if you're doing a lot of compiling from source. If your /tmp doesn't have much space, the process of installing many large apps, or compiling large apps (or many small ones at once) will slow down because the temporary "workbench" is too small for the work at hand, kinda like trying to prepare a meal on the same kitchen counter where two days worth of unwashed dishes still wait to be dealt with. It can be done, it's just slower, because you don't have room.

The point is, these separate partitions are meant to control drive space usage under certain specified conditions-- but the drives you're talking about don't have enough space that controlling space usage in this way is of any use to you. You have to control space usage in a different way... by installing fewer programs, and by reliably backing personal data files off the PC, because with only 4-6 GB of space, it does not matter whether /home is in a separate partition, you are simply not going to have room for a whole bunch of music or video files, or games installed via Wine or WineX (which are by default installed into your /home/username/.wine/c/program files folder).

The smallest "reasonable" Mandrake 9.2 install I've ever done-- "reasonable" referring to what I installed from the 3 CDs: both KDE and GNOME, plus XFce and fluxbox, no servers except Samba, few games except what come with KDE and GNOME, Quake 1 & 2, and Frozen Bubble, OpenOffice.org, development tools, some console-based apps, plus of course the core system and a few small extras of apps that I wanted to see if I liked them) came to about 3GB. This was on a 4.2 GB partiton, so I consider that a reasonable install, insofar as it left me enough room to save some personal files in my $HOME folder (not that I do that-- I mount my "storage" partition into my $HOME from a separate partition, so this worked for me in that I could just save a fast text file to $HOME without having to surf, which was what I wanted), and still felt that I had some space to install programs that I might come across in the future.

But not much space, and I did have to get a larger second drive to store things like downloaded files or large projects that I was working on, or to install Wine games (or even native Linux games-- I play Neverwinter Nights, and the install for that is 2GB, although I can put it wherever I want, so it does not have to live in the fixed / tree).

So what I'm saying is that this is mostly a question for the future. Set up the systems and see how they are used, then when you get more space, it will be clearer what partitions need to be moved to the larger digs. But at this point, you flatly don't have enough room to guess, and making a big /opt partition when it may turn out that you really needed a larger /tmp or /home partition (not that either of these is going to be "large" under these conditions) is only going to cause you more trouble than you need for a first experimental install on behalf of new users who may already be nervous about how well this all is going to work in the first place.

Hope this helps.