On 2018-12-07 01:43, Doni Crosby wrote:
This is qemu-kvm? What's the cache mode being used? It's possible the
usual write guarantees are thwarted by VM caching.
Yes it is a proxmox host running the system so it is a qemu vm, I'm
unsure on the caching situation.
On the note of QEMU and the cache mode, the only cache mode I've seen to
actually cause issues for BTRFS volumes _inside_ a VM is 'cache=unsafe',
but that causes problems for most filesystems, so it's probably not the
issue here.
OTOH, I've seen issues with most of the cache modes other than
'cache=writeback' and 'cache=writethrough' when dealing with BTRFS as
the back-end storage on the host system, and most of the time such
issues will manifest as both problems with the volume inside the VM
_and_ the volume the disk images are being stored on.
