[CentOS] CentOS, XFS, VirtualBox - can they just get along?

Wed Apr 25 17:07:03 UTC 2012
Emmanuel Noobadmin <centos.admin at gmail.com>

On 4/26/12, Boris Epstein <borepstein at gmail.com> wrote:
> Hello all,
> I am running VirtualBox 4.1 on CentOS 6 and I got this warning that putting
> your VM's into an XFS filesystem is risky. I have also heard some rumors on
> the net to this effect. Does anyone know in more detail what's behind those
> rumors?

I came across the same warnings while looking up on using XFS as the
fs on storage nodes. IIRC it has to do with caching and flushing to

>From what I understood:

VM caches writes before sending it to the virtual disk.
Host's XFS does delay logging to address performance issue before
sending it to the HDD
HDD caches writes for performance and may not respect commands that
demand it turn off caching and flush writes.

If a power cut occurs, in the absence of a BBU HBA, it seems that it
is indeterminable if the last few writes had been committed and in
what sequence and usually means a corrupted VM.