Hi, On Sun, 12 Jun 2016 18:46:55 +0200 l...@gnu.org (Ludovic Courtès) wrote:
> So we assume the latest GRUB always “works”, and we generate a grub.cfg > with a menu list all the older generations, which is rather convenient > from the UI viewpoint, I think. It's definitely convenient. Back when I enabled home encryption GuixSD didn't boot multiple times. Having the older generations there saved me from a system reinstallation / restore. However, I think the actual point is to have all the "update" actions be atomic. Because there's something in the Linux kernel config (only on GuixSD; works just fine on Ubuntu) which makes my laptop crashy (on the first larger disk write after standby wakeup) I have some experience with Guix non-atomicity and let me tell you it's not good. (Just the other day it broke the substitute cache - so I couldn't use substitutes at all anymore; I've since found and deleted the cache directory contents) Therefore, while I wouldn't replace (or re-symlink) the entire /boot on guix reconfiguration (it might be on its own partition, too), it *may* be useful to use include files and put these there atomically, one file per version. I'm not sure whether grub supports something like "include *.inc" with wildcards but that would be an idea. For the record: atomically creating an important file means: - write content into tempfile, if necessary into a subdir of the correct drive (where the finished file will be) - fdatasync - rename tempfile to have finished name (atomically) Also without the include files it's fine to use one larger grub.cfg and update it like described. I think that the monolithic grub.cfg is fine.
