On Fri, Jun 26, 2020 at 04:58:19PM +0200, Vitaly Zaitsev via devel wrote:
I'm strongly against this proposal. BTRFS is the most unstable
file
system I ever seen. It can break up even under an ideal conditions and
lead to a complete data loss. There are lots of complaints and bug
reports in Linux kernel bugzilla and Reddit.
That certainly would be concerning, but do you have citations on this? I did
a search on reddit and did not find a significant number of such complaints
in the top results -- in fact, mostly positive reports. For kernel bugzilla
issues, do you have numbers compared to other filesystems?
My Reddit search _did_ turn up this presentation from Usenix:
https://www.usenix.org/conference/atc19/presentation/jaffer
From that in part:
* ext4 has significantly improved over ext3 in both detection and recovery
from data corruption and I/O injection errors. Our extensive test suite
generates only minor errors or datalosses in the file system, in stark
contrast with [a 2005 paper], where ext3 was reported to silently
discard write errors.
* On the other hand, Btrfs, which is a production grade filesystem with
advanced features like snapshot and cloning, has good failure detection
mechanisms, but is unable to recover from errors that affect its key
data structures, partially due to disabling metadata replication when
deployed on SSDs.
[...]
* We notice potentially fatal omissions in error detection andrecovery for
all file systems except for ext4. This is concern-ing since technology
trends, such as continually growing SSDdrive capacities and increasing
densities as QLC drives whichare coming on the market, all seem to point
towards increas-ing rather than decreasing SSD error rates in the
future. [...]
--
Matthew Miller
<mattdm(a)fedoraproject.org>
Fedora Project Leader