I’d been using ZFS with Void linux on both my laptop and desktop for a couple of months. And ZFS is cool! But I’m thinking not great for my use case, especially for my laptop with it’s more constrained resources. Memory usage was a real problem, even after imposing low ARC limits. And the kernel module compile time was long enough to be a bit annoying, especially for a few kernels (I like to keep the last few around, to be safe) as it happens fairly often on a rolling release.
I switched the laptop to LUKS/btrfs a couple of days ago. And I’m thinking that was the correct choice for that. And now I’m considering doing the same for my desktop. As they seem comparable but btrfs is in-kernel and seemingly more system resource friendly. But before doing so I figured I’d ask the community about it. Maybe some important factors or features for either setup that I might not be considering.
Here’s the stuff I care about. All of which both offer, but I’m not an expert at either and I don’t know how equal they are.
- Disk encryption. For ZFS everything (except the EFI partition) is encrypted. I use ZFSBootMenu in this scenario. For the btrfs setup I have the kernel/initramfs on an ext2 partition. I do not store any decryption keys in the initramfs. I know grub can decrypt LUKS with limitations, but I prefer this setup. And it feels secure enough to me. Any pitfalls I’m missing?
- Pools/subvolumes
- Snapshots. ZFSBootmenu has an option to load a snapshot. For btrfs it looks like I’d need to create a subvolume from a snapshot, which in a recovery situation might mean doing this from recovery media. That’s ok, given this is an unlikely thing to encounter. But if anyone knows of an easier way, I’d love to hear it.
- CoW
- RAID 1
- Compression is nice, especially for the laptop
Edit: typo in title.
I generally point people away from both the solutions you’re asking about and the thing you’re doing.
If you are concerned about recovering from a failure then everything you’re talking about doing will make it very hard to complete using standard tools and techniques and very easy to lock yourself out of completing.
If you’re not concerned about recovering from a failure then why are you doing what you’re talking about doing?
A more functional solution for a laptop or desktop might be ext4 with dm-crypt or whatever and nightly backups. Another fix might be moving towards software that doesn’t require the capacity to reverse updates frequently.
Fine points. And I am considering that simplicity might be worth it. Except for:
Totally solid advice, but I love my rolling release distro though. So for the time being I’m willing to accept the associated risk.