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It seems that btrfs is being phased out of fedora. It looks like Fedora will be moving to stratis storage over the next year or two. Btrfs is nice but it's raid

It seems that btrfs is being phased out of fedora. It looks like Fedora will be moving to stratis storage over the next year or two. Btrfs is nice but it's raid5/6 support still seems shaky and there's odd corner cases that apply to all btrfs setups (getting stuck when free space is low is mostly resolved but can still occur).

ghaff 20d ago
I'm not super-plugged into Fedora these days. Red Hat has long been pretty comfortable with a more conventional file system (think it's still XFS out of SGI by default) plus volume management for RHEL. ZFS was a non-starter for licensing reasons and Oracle; btrfs just wasn't there. I suspect things could have played out differently had Oracle relicensed ZFS once upon a time but that ship has likely sailed in a variety of ways.
- tharkun__ 19d ago
  XFS is a default filesystem in a production system? Really? XFS was dead to me 20 years ago. The only time I ever actually verifiably lost data to a system crash was on XFS. I had actual zero length files with XFS after a crash. Lost actual data. But the file system was in totally happy consistent metadata state. Never ever would I ever consider that filesystem ever again. The ominous "reisserfs" everyone complained about? Never lost a single byte of data to it even when I pulled the plug in the middle of a write operation to test it. No issues with ext4, no experience with btrfs.
  - pram 19d ago
    The main problem with ReiserFS is Reiser killed his wife so it is unmaintained.
    - ghaff 19d ago
      There is that. I think ReiserSF used to be the default that SUSE used. These days, it seems to be btrfs for root and XFS for everything else.
    - tharkun__ 18d ago
      That's why I called it "reisserFS" and not reiserfs. I am well aware of the controversies because of what he did on the non-technical side. I am also of course for a very long time by now not using it any longer. I was merely talking about the experience with XFS "back in the day" and yes I was on reiserfs and then XFS "came up" and I changed my home partition to that, coz I was looking to move off of reisserfs. Power outage. Boom, lost half my home dir. Suddenly lots of totally fine metadata wise files had null length. I did go back to reiserfs until ext4 was stable enough after that. I will never try XFS ever again, sorry. Loosing data is the thing that a file system can't do to me if they want to "retain my business" so to speak. And yes, reiserfs I actually tested and had survive some power outages totally fine too. I believed the XFS hype too much without proper testing. My bad I guess in that sense. We were all young once. But also: Never again XFS ;)
  - ghaff 19d ago
    You may not believe it but it is true: https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/7/html/storage_administration_guide/ch-xfs https://docs.redhat.com/en/documentation/red_hat_enterprise_... I vaguely know some of the backstory of moving off ext4 (as default). As I understood it at the time, it was less focused on some of the larger systems Red Hat was interested in.
fpoling 20d ago
Stratis does not support data integrity checksums. There is dm-integrity hack but it slows down the write speed by halve.
ghaff 19d ago
I no longer have the direct relationships with storage folks at Red Hat that I once did and that stuff may all be over on the IBM side anyway. Stratis (which I wasn't familiar with) does seem to be designed with the intention of bringing a lot of pooling etc. on top of a conventional file system but haven't really looked at or talked to anyone in the storage groups recently. Conventional LVM was pretty old and really designed for a different time.

ghaff 20d ago

I'm not super-plugged into Fedora these days. Red Hat has long been pretty comfortable with a more conventional file system (think it's still XFS out of SGI by default) plus volume management for RHEL. ZFS was a non-starter for licensing reasons and Oracle; btrfs just wasn't there. I suspect things could have played out differently had Oracle relicensed ZFS once upon a time but that ship has likely sailed in a variety of ways.

tharkun__ 19d ago
XFS is a default filesystem in a production system? Really? XFS was dead to me 20 years ago. The only time I ever actually verifiably lost data to a system crash was on XFS. I had actual zero length files with XFS after a crash. Lost actual data. But the file system was in totally happy consistent metadata state. Never ever would I ever consider that filesystem ever again. The ominous "reisserfs" everyone complained about? Never lost a single byte of data to it even when I pulled the plug in the middle of a write operation to test it. No issues with ext4, no experience with btrfs.
- pram 19d ago
  The main problem with ReiserFS is Reiser killed his wife so it is unmaintained.
  - ghaff 19d ago
    There is that. I think ReiserSF used to be the default that SUSE used. These days, it seems to be btrfs for root and XFS for everything else.
  - tharkun__ 18d ago
    That's why I called it "reisserFS" and not reiserfs. I am well aware of the controversies because of what he did on the non-technical side. I am also of course for a very long time by now not using it any longer. I was merely talking about the experience with XFS "back in the day" and yes I was on reiserfs and then XFS "came up" and I changed my home partition to that, coz I was looking to move off of reisserfs. Power outage. Boom, lost half my home dir. Suddenly lots of totally fine metadata wise files had null length. I did go back to reiserfs until ext4 was stable enough after that. I will never try XFS ever again, sorry. Loosing data is the thing that a file system can't do to me if they want to "retain my business" so to speak. And yes, reiserfs I actually tested and had survive some power outages totally fine too. I believed the XFS hype too much without proper testing. My bad I guess in that sense. We were all young once. But also: Never again XFS ;)
- ghaff 19d ago
  You may not believe it but it is true: https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/7/html/storage_administration_guide/ch-xfs https://docs.redhat.com/en/documentation/red_hat_enterprise_... I vaguely know some of the backstory of moving off ext4 (as default). As I understood it at the time, it was less focused on some of the larger systems Red Hat was interested in.

fpoling 20d ago

Stratis does not support data integrity checksums. There is dm-integrity hack but it slows down the write speed by halve.

ghaff 19d ago

I no longer have the direct relationships with storage folks at Red Hat that I once did and that stuff may all be over on the IBM side anyway. Stratis (which I wasn't familiar with) does seem to be designed with the intention of bringing a lot of pooling etc. on top of a conventional file system but haven't really looked at or talked to anyone in the storage groups recently. Conventional LVM was pretty old and really designed for a different time.