I’m installing 3x2TB HDDs into my desktop pc. The drives are like-new.

Basically they will replace an ancient 2tb drive that is failing. The primary purpose will basically be data storage, media, torrents, and some games installed. Losing the drives to failure would not be catastrophic, just annoying.

So now I’m faced with how to set up these drives. I think I’d like to do a RAID to present the drives as one big volume. Here are my thoughts, and hopefully someone can help me make the right choice:

  • RAID0: Would have been fine with the risk with 2 drives, but 3 drives seems like it’s tempting fate. But it might be fine, anyhow.
  • RAID1: Lose half the capacity, but pretty braindead setup. Left wondering why pick this over RAID10?
  • RAID10: Lose half the capacity… left wondering why pick this over RAID1?
  • RAID5: Write hole problem in event of sudden shutoff, but I’m not running a data center that needs high reliability. I should probably buy a UPS to mitigate power outages, anyway. Would the parity calculation and all that stuff make this option slow?

I’ve also rejected considering things like ZFS or mdadm, because I don’t want to complicate my setup. Straight btrfs is straightforward.

I found this page where the person basically analyzed the performance of different RAID levels, but not with BTRFS. https://larryjordan.com/articles/real-world-speed-tests-for-different-hdd-raid-levels/ (PDF link with harder numbers in the post). So I’m not even sure if his analysis is at all helpful to me.

If anyone has thoughts on what RAID level is appropriate given my use-case, I’d love to hear it! Particularly if anyone knows about RAID1 vs RAID10 on btrfs.

  • antsu@discuss.tchncs.de
    3·
    7 hours ago

    Briefly addressing the RAID types you mentioned:

    • RAID-0: OH NO OH GOD PLEASE NO AHHHHHHH
    • RAID-1: There’s nothing wrong with it, but it feels very weird to me that BTRFS can do RAID-1 over 3 disks. It’s still technically 2 copies of every block, meaning you can in theory lose any single drive and still recover the data, but idk, it just feels wrong.
    • RAID-10: Again, weird that BTRFS allows this with an odd amount of disks. From what I can find, this has no advantage over RAID-1 with 3 disks and can in fact perform worse.
    • RAID-5: It’s probably fine if you have backups, and you get the most usable space out of your disks, but performance will take a hit, and scrubs are terribly slow.

    Now, you mentioned not wanting ZFS due to complexity, but really, it is no more complex to manage than BTRFS. It’s fairly easy to get it working on any modern Linux distro (Ubuntu has support out-of-the-box, Debian has it packaged as a DKMS module, Arch has it in AUR, and so on).

    With ZFS, you could create a RAID-Z1 (equivalent to a RAID-5) without any of the performance penalties or risks that BTRFS RAID-5 has. Both have pretty much them same features, with the main difference that ZFS can’t be “re-balanced” to a different disk layout like BTRFS can, but it will also generally not corrupt your data if you look at it wrong. Everything else maps pretty much 1:1 between them. Both support:

    • Transparent compression
    • Transparent checksums
    • Scrubbing
    • Snapshots
    • Block-level transfers (btrfs-send / zfs-send)
    • Fairly intuitive CLI
    • Filesystem (BTRFS) == Pool (ZFS)
    • Subvolume (BTRFS) == Dataset (ZFS)
    • GnuLinuxDude@lemmy.mlOP
      1·
      7 hours ago

      My concern with ZFS is I use Fedora, so the kernel updates really frequently. I know that it kicks ass, but I just like having it straightforward in my kernel that I already have installed so that I never have to deal with a

      If kernel module can not be loaded, your kernel version might be not yet supported by OpenZFS. An option is to an LTS kernel from COPR, provided by a third-party. Use it at your own risk:

      situation. (https://openzfs.github.io/openzfs-docs/Getting Started/Fedora/index.html)