The 4.9 kernel has been released

Posted Dec 12, 2016 7:47 UTC (Mon) by kragil (guest, #34373)
Parent article: The 4.9 kernel has been released

XFS is getting a lot of love lately (even from Oracle). Is that a sign that BTRFS is not all it was supposed to be (RAID5+ won't work etc) and the community is moving more in the direction of XFS?

The 4.9 kernel has been released

Posted Dec 12, 2016 8:07 UTC (Mon) by tim_small (guest, #35401) [Link] (2 responses)

It'd certainly be nice to have two Linux file-systems with dedup, native snapshots (without licensing and architectural complications). I look forward to testing these feature in XFS once they're complete and upstream.

Over the weekend I hit two bugs on btrfs systems, and cursed my choice of file-system.

One was a CPU hang during btrfs send - but after a quick web search, this turned out to be a performance bug due to a heavily fragmented file (>10,000 fragments), and was pretty easily fixed.

The other looked like filesystem corruption (bad checksums), but whilst backing up the filesystem prior to repair it turned out that the RAM was bad in this box - other filesystems would have gone on silently corrupting, whereas btrfs caught this early.

So what looks like btrfs losing badly twice, was actually one win to btrfs, and I'll call the other one a narrow defeat. In my experience now that Facebook are deploying it in production btrfs is stabilising fairly quickly.

The 4.9 kernel has been released

Posted Dec 12, 2016 21:10 UTC (Mon) by niner (subscriber, #26151) [Link] (1 responses)

When trying out btrfs send/receive for the first time I stumbled over some corruption in my file system. Turned out it was just a lost extent that wasn't referenced by any file and could be fixed easily by btrfsck. It made me question our decision to deploy btrfs on our servers and use send/receive for backups. But then I tried it on my desktop, too and had to shrink my ext4 partition. Which made me discover several corruptions of the ext4 file system. And that's on my desktop which never suffers a power loss while my laptop has endured much over the years in which I've had all my stuff on btrfs.

The result was that send/receive is awesome, file systems are fallible and the important bit is having backups and backups of the backups.

The 4.9 kernel has been released

Posted Dec 13, 2016 11:29 UTC (Tue) by bluss (guest, #47454) [Link]

When minor corruptions like that are a normal occurence, file systems should be designed to handle them in their regular use, without having to run full restore from backup. (If fsck handles it, it's fine).