I'm off to DebConf next Thursday. I'm looking forward to it; I could do with a change of scenery and some time with friends. I'm having my usual "What do I need to bring?" worries and I got to wondering about which laptop to bring - since last year I've gained an EEE 901, but I still have my Toshiba R200.
In general I'm using the EEE these days when I'm not using my desktop - it's much more convenient to throw in an overnight bag. However the keyboard and screen are too small for hard core use. Which suggests I should take the R200. Except the EEE battery life is great and a small laptop is handy for use in talks. So I think I'll bring both. Which led me to think about the fact I don't use the R200 that much these days and why that is. And it's partly about all the various bits that live in my home directory that mean switching machine is a sort of context shift. That applies to my desktops too.
And then I had a thought. Both laptops have built in SD readers. So do both of the desktops I regularly use. Why not just put my home directory on an SD card? These are machines that I don't log into remotely, so the card being removed when I'm not in front of the machine isn't a problem (it means I have to log out, but I think that's acceptable). I'm not totally sure of the speed of the readers in the various machines, but I guess the best way to find out if it's doable is to try it.
So, various things to ponder:
- Card size. Do all my readers support SDHC? In which case I should get an 8G or 16G card. Otherwise 1G is probably the safest maximum size? I suppose I can order one of each; they'll get used somewhere even if it's not for this.
- Card make. I don't want something that's going to die after a week of use; I'll try to ensure cache directories and similar are symlinks to a local piece of storage but I don't have a feel for the number of writes my home directory normally sees. I like Crucial for RAM. How's their flash? Integral? Or just bite the bullet and accept Sandisk are going to be best, if pricey?
- Filesystem. ext3? Or will the journal kill the card faster - I understood this was less of a concern these days. Are ext4 or btrfs ready for this sort of use? Perhaps this is the right time to try; I can keep backups on every machine that uses the card easily enough.
- Crypto. I may as well encrypt the card for security as I doubt that'll end up being the bottleneck for access. Is dm-crypt the right thing? libpam-mount looks like it might let me tie things together in a simplish fashion.
- Union mount? It might be nice to have a basic home directory on every machine so I can login even if I don't have my card with me. Or have local configuration bits specific to each machine. Perhaps something for a bit further down the line - I'm not sure any of the unionfs options are in mainline kernels yet?
I suppose I'll do some card manufacturer investigation and try and get a couple of cards ordered in time to play with over DebConf.