Which file system? Status 2020

[typewriter]

I intend to start my UNRAID server with 4 Seagate Exos X16 16tb drives - one as parity.

I read some older post from 2017 what's better: XFS or btrfs. 

There was posted that btrfs s would still have some issues since it's in development.

Has this changed meanwhile?

 

 

[hawihoney]

Just my personal two cents:

 

After migrating three Unraid servers (over 30 disks) from ReiserFS to XFS years ago, I never had one single problem with that file system.

 

BTRFS was running a cache pool out of two disks here since that same time. BTRFS gave me lot's of problems in that same time. There are still workarounds one needs to know (cache settings to avoid massive writes on some NVMe disks, needs balance twice to work properly in some configurations, etc. etc.). Whenever one BTRFS formatted disk fails within a cache pool, this results in massive writes on the remaining healthy disk before you can even replace the failing disk (who designs that?). This year I had two cases where a BTRFS disk dropped from the cache pool. Unraid didn't notice that and works as if nothing had happened - the disk was simply gone silently.

 

I'm trying hard to get a BTRFS-less world here. In fact I already moved all non-performance-critical Dockers and VMs to the array. And I hope the day would come, when there's a XFS or other FS driven cache pool possible.

 

I consider BTRFS as under construction, not ready at all.

 

As I said, this is my personal opinion build from my personal experience.

 

Edited November 20, 2020 by hawihoney

[spazmc]

I only have a single cache disk.

So I'm using XFS no problems here.

[hawihoney]

I know that single disk cache with XFS is possible, but I want more savety: Dual disk parity for the array and dual disk cache. Later is only possible with BTRFS.

 

The last Docker on Cache here is Plex with it's trillion files spread over 215 GB in our case. I'm currently rethinking that. Perhaps I move Plex to the array as well, drop the Cache completely and live with that performance degration until further features become built into Unraid - I hope.