| 5 May 2023 |
 @nikstur:matrix.org | Mhmm that's a good point. | 21:33:07 |
| @nikstur:matrix.org | But maybe if we teach the systemd tools the locations of the files (like /etc/os-release, repart definitions etc.) it expects, don't we get close enough? | 21:35:45 |
| @nikstur:matrix.org | * But maybe if we teach the systemd tools the locations of the files (like /etc/os-release, repart definitions etc.) it expects in the nix store, don't we get close enough? | 21:36:25 |
 @elvishjerricco:matrix.org | nikstur: Thing is, that's not a whole lot different than just... putting those files in the initrd, from a practical perspective | 21:50:42 |
| @nikstur:matrix.org | Right right right. I think I was a little (very) slow on this. Let me think about it a little more... | 21:56:40 |
| @elvishjerricco:matrix.org | I do kinda wonder if we should be trying to reduce the fsNeededForBoot space. Like, a lot of the problem is that systemd wishes that all you needed in initrd was / and /usr, while in nixos we have a whole list of mountpoints that need to be there | 21:59:51 |
| @elvishjerricco:matrix.org | How much of that stuff is actually needed though? Like I think the main reason we need /var/lib is because of the users-groups stuff we do in activation. But shouldn't that stuff really be handled at the same level as systemd-sysroot? i.e. during ordinary stage 2 systemd units? | 22:00:48 |
| @elvishjerricco:matrix.org | (In fact, that's a good example because we already have a PR to change part of that one: https://github.com/NixOS/nixpkgs/pull/223932/files/034ae4044941f507dcabd5f20753d6c786f925b6..31361e90bc151eba286ffcdafdaed89df7c77de6?notification_referrer_id=NT_kwDOABTWvLI2MDE5MzMyOTc4OjEzNjU2OTI¬ifications_query=is%3Aunread) | 22:01:15 |
| @elvishjerricco:matrix.org | * (In fact, that's a good example because we already have a PR to change part of that one: ) | 22:01:20 |
| @elvishjerricco:matrix.org | * (In fact, that's a good example because we already have a PR to change part of that one: https://github.com/NixOS/nixpkgs/pull/223932) | 22:01:33 |
| @elvishjerricco:matrix.org | * How much of that stuff is actually needed though? Like I think the main reason we need /var/lib is because of the users-groups stuff we do in activation. But shouldn't that stuff really be handled at the same level as systemd-sysusers? i.e. during ordinary stage 2 systemd units? | 22:03:02 |
 @uep:matrix.org | Systemd is all about unbundling serial things (ball of script) into separate items with finer-grain dependency graphs | 22:36:10 |
| @uep:matrix.org | well, the "init system" part of systemd is | 22:36:18 |
| @uep:matrix.org | So, like, yeah... decouple away | 22:36:37 |
| @uep:matrix.org | At some point in this process, perhaps here where things potentially change between stage 1 and 2, we hit coupling and compatibility issues with a stage 2 that needs to work with scripted stage 1 still? | 22:38:39 |
| 6 May 2023 |
 @mberndt:matrix.org | Hey, so I was looking into making a test for the stratis root fs support that I'm trying to get merged, and I figured that the easiest way to do that is to tweak the lvm2 test that already exists.
https://github.com/NixOS/nixpkgs/blob/master/nixos/tests/lvm2/systemd-stage-1.nix | 16:00:30 |
| @mberndt:matrix.org | But I' confused, because it looks like a logical volume is created in line 90, and then a single file is created in that volume, and then he reboot into that volume | 16:02:19 |
| @mberndt:matrix.org | How can he boot from a volume that doensn't have anything in it? | 16:03:15 |
| @mberndt:matrix.org | * But I' confused, because it looks like a logical volume is created in line 90, and then a single file is created in that volume, and then it reboots into that volume | 16:03:32 |
| @mberndt:matrix.org | * How can it boot from a volume that doesn't have anything in it? | 16:04:51 |
| @elvishjerricco:matrix.org | mberndt: The root fs in nixos tests usually doesn't contain the OS. Instead, /nix/store is mounted as a 9p network file system from the host, so that the VM uses the host nix store instead of wasting time and space on a disk image | 16:06:00 |
| @mberndt:matrix.org | oh wow | 16:06:42 |
| @elvishjerricco:matrix.org | (that's only mostly true; in reality it's usually actually an overlay fs where the lower dir is the 9p file system and the upper dir is in ram or something) | 16:06:44 |
| @mberndt:matrix.org | that's clever | 16:06:48 |
| @mberndt:matrix.org | And so the nix store is already mounted in the initramfs? | 16:07:37 |
| @elvishjerricco:matrix.org | yea | 16:07:46 |
| @elvishjerricco:matrix.org | mberndt: Actually, it looks like that lvm test is currently failing https://hydra.nixos.org/job/nixos/trunk-combined/nixos.tests.lvm2.lvm-thinpool-sd-stage-1-linux-latest.x86_64-linux | 16:11:18 |
| @elvishjerricco:matrix.org | I think probably precisely because it's not doing what I just described :P | 16:11:28 |
| @elvishjerricco:matrix.org | As of recently, useBootLoader implies actually creating a root fs image containing the nix store | 16:11:47 |
| @mberndt:matrix.org | there goes my plan | 16:12:24 |
