tech question (btrfs) 

i'm reading about btrfs and still struggling to see any reason why i wouldn't just use ext4. there's gotta be a reason, right? i'm just not seeing any, especially if you just want a no-nonsense fs that you don't plan on interacting with all that much. snapshots and subvolumes and all that stuff just looks like a hassle rn

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tech question (which filesystem for which use case) 

one thing that i can't seem to find is, like, a simple breakdown chart listing the dis/advantages of various fs schemas and which ones to use when

reading all this shit just makes my eyes gloss over and mentally check out and decide to stick with ext4 for no reason other than "it works and i don't wanna deal with this rn"

like: ssd vs hdd, read vs write, sequential vs random, if striping or mirroring are used, etc... which would be best/worst?

tech question (a filesystem for my specific use case) 

with all that said, here's what i'm lookin' at, if someone doesn't wanna help generally but they know some specifics:

- 4x 8TB HDD
- probably destined for a NAS use case (i'm thinking snapRAID with 1 of them for parity? i might add another 3x 4TB if so)
- probably going to store a lot of media (music/movies/tv on one volume, photography/video work on another, documents/graphics/etc work on a third? not sure but whatever)

tech question (a filesystem for my specific use case, 2/) 

the 2nd half of the equation is i'm probably gonna use a 500gb sata ssd as a system drive, and i'm kinda strongly leaning to just putting / on there

but i was also considering using the ssd purely for VM stuff and instead installing arch to a 32GB usb drive, unraid-style -- with my desktop environment(s) as a guest under kvm? i might possibly need to hash that out a bit more but that's a separate issue

tech question (which filesystem for which use case) 

@trwnh offers several features lists for A LOT of fs.

But it's a flood of features not especially important and no conclusion (that would potentially violate NPOV). So more useful to answer questions like "what fs has ..." or "is ... has ...".

If speed is important, check and

You'll notice ext4 has good write performance. So if you write a lot, it's not bad to use it.

tech question (btrfs) 


i just use ext4 because like why wouldn’t you?

@rotor idk ext4 is "good enough" sure but there's gotta be a reason that people are excited about these fancy-schmancy new things, right?

@trwnh programmers get excited about any new shit whether it’s useful or not

@rotor ok but this is clearly useful and i'm just having trouble grasping how/why it's useful

although, i'm having much less trouble after someone shared this with me


idk i don’t do weird system stuff. I just plug the disks in and add em to fstab and call it done. ext4 suits my needs and i don’t have to waste three nights figuring out if it’s perfectly optimal

@rotor that's fair, i guess. that's also what i want for the most part. so far the most practical reason i've seen is that ext4 doesn't protect against bitrot

tech question (btrfs) 

@trwnh snapshots and subvolumes are the primary reasons to use btrfs. The other is that it is a CoW filesystem, which is superior to journaling.

tech question (btrfs) 

@matt yeah and i'd really like to understand what those are, why i'd use them, how i'd use them, etc

tech question (btrfs) 

@matt see this is a much better start to my research than the other 20 tabs i have open rn, this is good

tech question (btrfs) 

@trwnh I use BTRFS for my NAS RAID10 array for the bitrot protection. As long as you avoid RAID5/6 you should be fine.

Though if I were to rebuild the array today I would do it with ZFS

tech question (btrfs) 

@matt i'm pretty wary of zfs's inflexibility with regard to exact disk sizing, so i'd personally not use it unless it was for a fixed deployment. buying drives in batches is just not affordable for me, and it's probably a bit bad for reliability too bc it could lead to multiple failures within a short timeframe. being able to add different-sized drives at any time is pretty important to me

tech question (btrfs) 

@trwnh True, btrfs is definitely flexible in that regard.

tech question (btrfs) 

@matt also the other thing is like... it's easy to say things like "CoW is better than journaling" in an explainer but really hard to qualify that statement in a meaningful way to someone who doesn't really understand exactly what those are? and then what of the cases where you might want to disable CoW and/or journaling? there's nuance that gets stripped out of explainers but glossed over in the documentation

tech question (btrfs) 

@trwnh CoW let's you copy one file 1000x times and take up almost no additional space. If one of those copies is changed, only the "change" is saved to disk.

tech question (btrfs) 

@trwnh there are cases where CoW should be disabled, such as when running certain databases, but I'm not an expert on that.

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