Re: [Qemu-devel] [ceph-users] rbd cache + libvirt

[Andrey Korolyov]

On Mon, Jun 8, 2015 at 6:50 PM, Jason Dillaman <address@hidden> wrote:
> Hmm ... looking at the latest version of QEMU, it appears that the RBD cache 
> settings are changed prior to reading the configuration file instead of 
> overriding the value after the configuration file has been read [1].  Try 
> specifying the path to a new configuration file via the 
> "conf=/path/to/my/new/ceph.conf" QEMU parameter where the RBD cache is 
> explicitly disabled  [2].
>
>
> [1] 
> http://git.qemu.org/?p=qemu.git;a=blob;f=block/rbd.c;h=fbe87e035b12aab2e96093922a83a3545738b68f;hb=HEAD#l478
> [2] http://ceph.com/docs/master/rbd/qemu-rbd/#usage
>

Actually the mentioned snippet presumes *expected* behavior with
cache=xxx driving the overall cache behavior. Probably the pass itself
(from cache=none to proper bitmask values in a backend properties) is
broken in some way.

CCing qemu-devel for possible bug.