New desktop build, need some suggestions/help

don't worry about ssd write cycles modern ssd are not that bad

as for lvm I don't think it has any usefulness with btrfs as btrfs by itself has almost all features of lvm

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as for how to add devices to btrfs I think this articles explains it

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Iā€™m really confusedā€¦how would I be able to utilize the 2 HDDs, unless I combine their respective storage capacities into one logical volume? Otherwise, Iā€™d have to mount /home/user1 to one HDD and then /home/user2 to the other HDD - which really doesnā€™t make much sense since the two HDDs are of different storage capacities. Further, Iā€™m not planning on having more than one user account on the system, so not quite sure how best to utilize all 3 HDDs?

use btrfs device add to combine three disks in one partition.

read about btrfs device add

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Thanks for the tip, reading up on this now!

Ok, Iā€™ve been reading up on btrfs on arch, and Iā€™m finding some conflicting infoā€¦some sources indicate that btrfs device add with different storage capacities limits to the lowest common storage capacity denominator, whereas others are showing that the full storage capacity will be used when rebalanced after the device is added. Can anyone confirm?

Additionally, when running the btrfs device add command, you have to specify both the /dev/sdX path and then a mount point like /mnt or whatever you define. For example:
btrfs device add /dev/sdb1 /mnt and then run the rebalance command. However, doesnā€™t this effectively silo the storage capacity to the/mnt path only? Or does it somehow expand the volume to include the original system storage deviceā€™s capacity and the new storage device capacity into one continuous volume, regardless of the mount point specified in the btrfs device add command?

:confused:

Edit: Found this:

I believe this is a similar use-case for meā€¦in that I have 3 drives with very different performance characteristics. Is it possible to keep the ssd as the system btrfs, then combine the two hdds as one btrfs volume that I can mount in fstab?

@dalto would you happen to know if this would work? Primary btrfs on SSD on clean install, then somehow combine the 2 HDDs as another ā€œsingleā€ btrfs volume? Not sure Iā€™m asking the right question, but trying to conceptualize the idea of sdd as one volume, and the 2 hdds as another single volume (a la raid 0 or lvm) but with 2 btrfs volumes instead?

Yes, it is possible. If you donā€™t want redundancy but want the total space available you can just create a btrfs filesystem on one of the HHDs and then add the other drive to it.

btrfs is a weird command in that it often needs a mount point to work. It doesnā€™t mean that the mountpoint is the only thing it impacts. It just needs a reference to a mounted subvolume to work.

In other words you can use the mountpoint from any subvolume, but the disk will be added to the full btrfs volume, not just that subvolume.

Cool! So, let me see if I understand the steps correctlyā€¦

  1. Fresh install Garuda on new build using SSD as primary storage device, and use the entire disk.
  2. After installation is complete, install 2 HDDs via sata and boot the machine.
  3. Format both HDDs as their own btrfs partitions.
  4. Mount hdd1 to /mnt/hdd1 (for example)
  5. Them mount hdd2 to /mnt/hdd1/hdd2 ?
  6. Then rebalance only hdd1+hdd2 together? (Not really sure thatā€™s how you do it - so very new to btrfs, iā€™m just guessing here).

I think Iā€™m getting lost on the actual steps I need to take of keeping the ssd as itā€™s own btrfs partition, and then somehow /etc/fstab mount the btrfs volume of HDD1+HDD2 into itā€™s own mountpoint off the root dirā€¦Sorry if Iā€™m being dense.

Gottit, that kind of makes senseā€¦

It has been a while since I have done this but I think you only format the first one. With the second one you just need the partition type set correctly then you add it to the first.

Not exactlyā€¦ You donā€™t mount 1 into 2. You just add 2 to 1. In other words if you mount the volume with a single disk at /mnt/monkey, you use sudo btrfs device add <2nd device path> /mnt/monkey

Use the UUID of the btrfs volume. You can get that from sudo btrfs filesystem show /mnt/monkey

With btrfs it is often easier to actually do things than it is to try to conceptualize them in advance.

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LOL Ok, I think I get it now:

  1. Format HDD1 as btrfs, and just make the proper partition on HDD2.
  2. Add the new HDD1 btrfs volume using UUID to /etc/fstab, for example /mnt/data
  3. btrfs add device HDD2 onto /mnt/data

But now how to rebalance only the two HDD drives in /mnt/data as a single volume?

As soon as you add them they will be a single volume.

To rebalance it you do:

sudo btrfs balance start /mnt/monkey
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Awesome! Thank you!

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Brother, you said a mouthful. :wink:

Iā€™ve never heard it put better. The more I investigated btrfs, the more I decided itā€™s not meant to be grokked by this 70-year oldā€™s remaining braincells. The stuff is very fluid. And thatā€™s very unsettling. Best to just do as you say.
:slight_smile:

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The more I keep falling down this rabbit hole, the truer these words becomeā€¦fun to learn tho!

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I though it was a desktop layout which i could steal :cry:

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